Using This Adventure
This is a small, one-shot adventure that you can fit into a more extensive campaign as a side quest or lead-in for a bigger adventure. The adventure assumes that the players are traveling upstream towards a river village, possibly because they heard the village was suffering some supernatural ailment. Alternatively, the town might just be a pit stop as part of a more extensive journey. The adventure provides names for the village, rivers, and lake. There is an assumption that the town is a typical small human village, but you can change any of these details to better suit your campaign setting.
Plot Points
This adventure is broken into multiple sections or plot points. Each plot point contains a Lead Up with information on how to transition into the plot point and an Aftermath detailing what may have changed due to the players' actions. The body of the plot point contains information on how to run the encounters and the loot and experience points that the players can earn. Many plot points also include description blocks that can aid in describing particular creatures and locations to the players.
Encounters
The significant encounters of these plot points feature encounter maps with markers suggesting the initial locations for players and creatures. The end of the document features larger versions of all these encounter maps and the stat blocks for the new creatures included in the adventure.
Traveling
In between plot points, the players will mostly be traveling along the river towards the source of corruption. The dangers they will face along their journey will change as they get closer to the source and choose different routes. The plot points include overland travel information you can use to run these traveling portions of the adventure. This includes random encounter tables, which you can roll on or handpick results from to suit the current situation.
River Hazards
Some of the encounters involve river hazards such as rapids and waterfalls. More information on how to use these hazards can be found in the River Travel section, along with guidance on running overland travel along rivers.
Adjusting the Difficulty
The baseline adventure assumes the players have a group of 4 characters somewhere in the level 6-8 range. If your party is smaller or of a lower level, there are alternative options for most encounters to reduce their difficulty. However, parties with characters mostly below level 5 will likely struggle due to the significant jump in character power at this level.
If the party is very large, at a higher level, or you simply want more challenging encounters, the alternative encounter options include means for scaling up their difficulty. However, even these options will quickly begin falling off in difficulty for characters level 10 and above.
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Table of Contents
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3Adventure Plot Points
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20Adventure Resources
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20River Travel
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21Creatures
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21Adventure Maps
Art Credit
- Fester Gnaw - Joseph Snouwaert
- All Maps - Joseph Snouwert
- Wooded River Landscape (1913) - Peder Mørk Mønsted
- A River Landscape At Dusk With And Figures Walking Along A Path Towards A Village To The Left, A Church In The Distance - Aert van der Neer
- Westvale Abbey - Min Yum, Wizards of the Coast
- Island (Avacyn Restored) - Jung Park, Wizards of the Coast
- Waterfall in the Münster Valley - Peter Birmann
- Frost Lynx - Ilse Gort, Wizards of the Coast
- Surge Mare - Sam Rowan, Wizards of the Coast
- Breaching Hippocamp - Christopher Burdett, Wizards of the Coast
- Choked Estuary - Vincent Proce, Wizards of the Coast
- Forest Stream (1896) - Peder Mørk Mønsted
- Spined Karok - Filip Burburan, Wizards of the Coast
- Necrotic Ooze - James Ryman, Wizards of the Coast
- Tierleben 1920 - Wilhelm Kuhnert
Adventure Plot Points
Adventure Summary
As the party travels along the Timberland River, they begin to see signs that something is tainting its waters and interfering with its flow. They may learn this by observing the river and noticing its tainted waters and the impact on the local wildlife. This unnatural influence is emphasized by an encounter with unusually dangerous and hostile river animals.
After this, the party arrives at the small village of Brookston further upstream. They will see how its residents are becoming racked with sickness due to the river's corruption. The villagers will be desperate for the party's help. They will be happy to provide them with general directions on reaching a lake upstream of the river where they believe the problem originates. If the players do some investigating and talk with the townsfolk, they can learn more about the corruption and other creatures lurking further upstream.
As the players follow the corruption upstream, they will quickly encounter the demonic beavers known as fester gnaws that cause the river's deterioration. After about of day of travel, they will also reach a fork in the river and have two primary routes to approach Timberland Lake. One will be a longer route with easier terrain along the Reedymane River, which will bring the players through kelpie territory. The other will be a direct but treacherous route through the domain of a mishipeshu.
Overland Map
When the party reaches the lake, they will have to find a way inside the fester gnaws' dam, which is the source of the river's corruption. Once they find their way inside, they will have to face off against the foulest creation of the beavers: their demonic, animated, wooden effigy.
The adventure concludes with the players destroying the dam and shattering the beavers' grip on the lake. You can include aftermath encounters wherein the players must hunt down the surviving beavers that are either attempting to flee or traveling downstream to attack the village directly.
Festering Wounds
The fester gnaws and their demonic allies can inflict a condition known as a festering wound upon creatures. It represents the fiendish corruption these creatures infect the water with but afflicting a creature instead. A creature can be afflicted with multiple festering wounds. At the end of its turn, a creature afflicted with one or more festering wounds makes a DC 15 Constitution saving throw. If it passes, it rids itself of all its wounds. If it fails, it takes 1d6 necrotic damage for each wound. The creature only makes this check once per turn, regardless of the number of wounds and sources of wounds. The wounds can also be cleared if a creature within 5 feet (including itself) uses an action to make a successful DC 15 Wisdom (Medicine) check.
1. Animal Attack
This is the jumping-off point for the adventure. It starts with the assumption that the party is traveling up a river, either using a small paddle boat or following it on foot.
Lead Up
As the party travels upstream along or on the river, characters with proficiency in Nature or Survival will notice the following characteristics of the river:
- Its water level is lower than usual, despite there not being a drought.
- The water has an unnatural murkiness to it.
- The riverside plants are twisted into menacing shapes.
- The small river animals act unusually aggressively, though they can't pose any real threat to the party.
Animal Attack
EXP Award: 4,800
After the party has had the chance to notice the anomalies in the river, they will find themselves subject to the predation of dangerous and hyper-aggressive river animals. These animals have an inhibited sense of self-preservation and advantage on any saves made against effects that charm or soothe them. The type of animal they are attacked by will depend on the setting you've chosen for this adventure, but listed below are the options for encounters with alligators, crocodiles, hippos, or jaguars.
Attacked by Crocodilians
The players are attacked by 2 giant crocodiles* or 3 giant alligators*. Each crocodilian will use stealth to approach a different character and attempt to catch them in a surprise attack. If the crocodilians are spotted, they will attack the nearest character. After a successful attack, a crocodilian will attempt to drag its target out into the water, using its death spin as often as possible.
Adjusting the Difficulty
Easier Encounter. Change the encounter to 6 crocodiles* or 2 giant alligators. Change the EXP Award to 2,000.
Harder Encounter. Change the encounter to 2 giant crocodiles and 3 crocodiles or 6 giant alligators. Change the EXP Award to 8,000.
Attacked by Hippos
The players are attacked by 3 hippos*. The hippos are not subtle in their tactics. They will charge the nearest player, preferring to engage from the direction of the water. If a player hanging back proves to be a significant threat, one or more hippos will break from their current target to run down the higher-priority character.
Adjusting the Difficulty
Easier Encounter. Change the encounter to 2 hippos. Change the EXP Award to 2,000.
Harder Encounter. Change the encounter to 5 hippos. Change the EXP Award to 8,000.
Animal Attack Encounter Map
Legend
- C: Crocodilian
- H: Hippo
- J: Jaguar
- P: Player's Starting Area
Attacked by Jaguars
The players are attacked by 3 giant jaguars*. The jaguars will try to ambush the players from the trees, prioritizing softer-looking targets. If a jaguar manages to grapple a player, it will drag its victim out into the river, if possible. Jaguars fighting at a clear disadvantage may retreat into the woodline to hide and attempt another sneak attack.
Adjusting the Difficulty
Easier Encounter. Change the encounter to 2 giant jaguars. Change the EXP Award to 2,000.
Harder Encounter. Change the encounter to 5 giant jaguars. Change the EXP Award to 8,000.
*See Creatures section for all stat blocks
Aftermath
The animal attack should serve as a strong indicator that something is amiss with the environment here if the party has not already determined that. Depending on how much further the group has to travel before reaching the town, they may run into additional dangers before completing this part of their journey.
Navigating to Brookston
Rate of Random Encounters: Every 6 Hours
Navigation DC: None if following river, 15 otherwise
Foraging DC: 10 with disadvantage unless the purify food and water spell is used while foraging
Description: During the journey to Brookston, the signs of the river's corruption are still subtle, with the most obvious being the unnatural hostility of the wildlife. The most direct route to the Brookston will be along the river, but the party may opt to try and cut inland to avoid the river. This will make navigation more difficult but give them a tactical advantage over any corrupted river creatures they encounter.
Once the players reach the town, award them 4,800 EXP.
Adjusting the Difficulty
Easier Encounters. Change the EXP awarded for reaching town to 2,000, and modify the following entries of the random encounter table:
- Change result 1 to 2 crocodiles, 1 hippo, or 1 jaguar
- Change result 2 to 1 giant crocodile, 1 hippopotamus gorgops, or 1 giant jaguar
Harder Encounters. Change the EXP awarded for reaching town to 8,000, and modify the following entries of the random encounter table:
- Change result 1 to 6 crocodiles, 3 hippos, or 4 jaguars
- Change result 2 to 2 giant crocodiles, 2 hippopotamus gorgops, or 3 giant jaguars
2. Brookston
This adventure stage gives the party the chance to stock up on equipment and learn more about the corruption plaguing the river. The town may be a pit stop for the party, or they may have had a specific reason for coming here, but as soon as they arrive, the danger the town is in will become apparent. Alternatively, this can serve as the start of the adventure if the players are already in town.
This adventure also assumes that the town is a standard, riverside hamlet populated mainly by humans. However, you can reimagine it to better fit your current campaign's context. For example, it could be a village of halflings, an isolated enclave of wood elves, or even a tribe of lizardfolk willing to accept help from outsiders.
Lead Up
Regardless of the kind of town you decide to use, the effects of the polluted river on its well-being should be dire and easy to detect.
Town Description
As you approach the settlement, you notice most outlying structures have been abandoned, and the inhabitants have pulled back to the village's center. The guards are uneasy, and many of them seem especially fatigued.
You notice a lack of trade goods on display when you enter the town, especially food and drink. Many of the villagers seem sickly and weak. Some look to you with hope and desperation, others with bitter distrust.
Interacting with the Townsfolk
The people here find themselves in a desperate situation. The food and water they depend on to survive have been tainted, and they will be desperate to trade for rations from outside locations. Besides food and water, players can obtain most essential goods and services here, including paddle boats and general information on the surrounding terrain and the path the river takes upstream.
Reactions to the party might be mixed amongst the different townsfolk. Some might be proud and distrustful; they will downplay the town's troubles and be hesitant to show signs of weakness. Others may be overly positive and unwilling to accept anything is wrong at all. The most helpful people will be the most desperate and pragmatic. If they sense that the players are capable adventurers, they will be more than willing to provide whatever goods, services, and information they can in exchange for their help.
If the players successfully learn information and gather resources useful for the upcoming adventure, you can award them 4,800 EXP. You can lower this to 2,000 EXP or increase it to 8,000 EXP depending on the party's level and how well they dug for information and resources.
Reward for Slaying Beasts
If the players describe the beasts that they slew to the town watch, the guards will reward them for helping to keep the surrounding area clear of hostile creatures.
Reward from Town Watch
- 100 gp worth of weapons or adventuring supplies
- potion of healing x2
Points of Interest
Assuming the players find amiable people to talk to, they should learn quite a bit of helpful information on the troubles with the river. If the players express an earnest desire to help alleviate the town's problems, they should have little difficulty convincing the townsfolk to divulge what they know. If a player spends an hour talking to people at any of the following locations, they can make a skill check to determine what they learn.
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Any Location: DC 10 Charisma (Persuasion) or Intelligence (Investigation) check. Something is corrupting the local waters, and as a result, clean food and water are scarce. Hunters and the village's guards warn that it's dangerous to wander into the wilderness.
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Watch Post: DC 15 Charisma (Persuasion) check, made with advantage if the player character has proficiency with a martial weapon. The town guards disclose that the local wildlife has become more hostile of late. As a result, people who travel upstream go missing, but their remains sometimes drift back downstream days later.
There's also supposedly a fiendish river monster that lives amongst the rocky waterfalls. Still, there have never been sightings of it straying this close to town. -
Hunter's Lodge: DC 15 Charisma (Persuasion) check, made with advantage if the player character has proficiency in Nature or Survival. A hunter or logger discloses that the local wildlife has become more hostile, and something has been deforesting large sections of woodland upstream.
There are also man-eating, fey horses that
supposedly live further upstream, and they've
become more brazen hunters of late. There
are legends of these horses being subdued
by cold iron tacks. However, the hunters
don't know much beyond that.
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Church or Other Spiritual Center: DC 15 Charisma (Persuasion) check, made with advantage if the player character has proficiency in Religion. A local spiritual practitioner discloses that something unnatural and otherworldly taints the environment.
If asked about the fiendish monster up the river, this individual will tell the player that the monster is a fierce guardian of the river that typically kills trespassers on sight. Though if the characters bribe it with copper or convince it that they are no threat to the rivers, they may be allowed to pass unharmed. -
Smith's Shop: DC 15 Charisma (Persuasion) check, made with advantage if the player character has proficiency in a set of artisan's tools. The local smiths disclose that they were once the apprentices of a smithing master who had a workshop further upstream. Unfortunately, shortly after the river became tainted, he was killed by the increasingly hostile animals, and his apprentices fled back to town to set up shop here. The apprentices can provide general directions as to its location.
If the apprentices are asked about the water horses up the river, they will disclose that their former master specialized in forging items made of cold iron. Additionally, he had created several cold iron riding tacks in the hopes of using them to capture and subdue a water horse. Those tacks are likely still at the abandoned shop in the woods.
3. Enter, The Fester Gnaw
As the players travel upstream, they will begin to notice more and more felled trees with significant gnaw marks in the wood. Finally, within a few hours of travel, they will encounter the primary antagonists of the adventure: the fester gnaws.
Lead Up
As the players travel, those on lookout duty with a passive Perception of 15 or higher will notice large tracks on the ground and the sound of wood being gnawed. A successful Intelligence (Nature) check on the tracks will reveal that some sort of oversized beaver has left them. Shortly after this, the party spots a chest made of rotting wood lying near the river bank pinned under a small tree. As the party approaches it, they will be attacked by fester gnaws.
When the players see them for the first time, you can use the following description:
Fester Gnaw Description
You find yourself staring at a monstrous beaver the size of a grizzly bear. It sports bony spines running across its body, and its massive teeth drip with an unnatural ichor. The beaver's eyes lock onto you with a fiendish malevolence as it moves to attack.
The Fester Gnaws
EXP Award: 4,800
Two Fester Gnaws* will lie in wait for the party, with a DC 15 Wisdom (Perception) check required to notice them. They will attempt to initiate the fight by dropping trees on as many party members as possible. If they are spotted early, they will try to draw the players in the range of a tree before dropping it on them.
Once the players close the distance, the fester gnaws will resort to using their bite attacks, focusing as much on one target as possible. If given the opportunity, they will fell more nearby trees onto any players they can, preferring to pin melee characters. They may adopt a strategy of having one fester gnaw draw the attention of melee players while the other focuses on felling trees.
Adjusting the Difficulty
Easier Encounter. Change the encounter to 1 Fester Gnaw. Change the EXP Award to 2,000.
Harder Encounter. Change the encounter to 3 Fester Gnaws. Change the EXP Award to 8,000.
*See Creatures section for all stat blocks
Fester Gnaw Encounter Map
Legend
- F: Fester Gnaw
- C: Chest
- P: Player's Starting Area
Aftermath
If the party defeats the fester gnaws and opens the chest, they will find the following items:
Items Found from Chest
- 600 gp, 500 sp
- potion of heroism
- potion of climbing
- 3 Copper Soldier Statues worth 100 gp each
After this point, the players will continue encountering fester gnaws as they travel upstream. A successful DC 15 Intelligence (Nature) check on their corpses will reveal that they don't have a natural origin. A DC 15 Intelligence (Religion) check will indicate that they are demonic in nature.
Time Sensitivity
Each day that passes, the players will notice the river becoming steadily more polluted and the danger of their environment slowly increasing. You can represent this by making each random encounter more dangerous or increasing the rate of random encounters each day the players spend in the wilderness. Either way, it should become apparent to the players that there is a cost to any delays in their journey upstream.
4. The Gunk Spawn
By the end of their first day of travel, the players should be close to a fork in the river. If they end their day of travel early or reach the fork faster than expected, you can use this encounter at that point. On the other hand, if the players have taken a beating during their first day of travel, and you don't think they'd survive another significant encounter, you can opt to throw this fight at them right after they've rested. In that case, you might consider increasing the difficulty to account for them having all their resources back.
Lead Up
As the players move further upstream, they see animal corpses decomposing into a gooey substance. A DC 15 Wisdom (Medicine) check will reveal magical corruption rotting the bodies. A DC 15 Intelligence (Nature) check will show that the substance is highly toxic and vulnerable to slashing damage.
If one of the players touches the ooze directly, have them make a DC 15 Constitution saving throw. On a failed save, they will take 1d6(3) necrotic damage and gain a festering wound, as described below.
As they travel further, they will see felled trees decomposing in a similar manner. They will encounter more fester gnaws and a new type of abomination not long after this: the gunk spawn.
When this occurs, you can read the following description:
Gunk Spawn Description
You spot what appears to be the remains of former adventurers being gnawed on by one of the demonic beavers. You also see two piles of the tainted ooze you've seen during your journey, except that these piles are moving of their own accord. They slowly lurch across land and water, absorbing any living thing they come into contact with, breaking it down into yet more ooze.
The Gunk Spawn
EXP Award: 4,800
As soon as they detect the players' presence, the fester gnaw* will attack, and three gunk spawns* will start lurching after the intruders. Once the gunk spawns are in range, they will unleash their gunk spewing breath on as many players as possible before closing in to grapple their victims.
Adjusting the Difficulty
Easier Encounter. Change the encounter to 1 fester gnaw and 1 gunk spawn. Change the EXP Award to 2,000.
Harder Encounter. Change the encounter to 2 fester gnaws and 3 gunk spawns. Change the EXP Award to 8,000.
*See Creatures section for all stat blocks
Gunk Spawn Encounter Map
Map Legend
- F: Fester Gnaw
- G: Gunk Spawn
- P: Player's Starting Area
Aftermath
After their first encounter with the gunk spawns, the players will continue to be harassed by these creatures as they continue their journey upstream. Players who investigate their remains can make the same skill checks to learn the same information described regarding the goo in the Lead-Up section. Additionally, they will learn the following new information: these gunk spawn appear to be the former remains of plants and animals with prolonged exposure to the tainted waters.
Players can loot the remains of the former adventuring party. If they've discovered the gunk's weakness to slashing damage, they will find the weapons left behind quite handy.
Loot Found from Adventurer Remains
- 60 pp, 500 gp
- A golden lockbox containing a small portrait worth 100 gp
- gloves of swimming and climbing
- potion of greater healing
- potion of water breathing
- Rapier
- Long Sword
- Plate Armor
5. Fork in the River
After about a day of travel and encountering the gunk spawn for the first time, the players will experience rocky terrain and discover a series of cliffs between them and the lake. The river splits at this point, with one route taking a longer, smoother path around the cliffs and another taking the more dangerous but direct route up the slippery rocks and cliffs.
The route through the rocky terrain is about 15 miles of rough terrain, meaning it would take the players a little over a day to traverse if they are moving at an average pace.
The smoother route is about 50 miles of clear terrain, meaning it would take the players around 2 days to travel it at an average pace. It doesn't connect directly to the lake but comes close enough that the players can use it as a reliable guide.
Increasing the Travel Time
If you want a longer adventure, you can increase the distance the players have to travel to reach the lake. The proportionate distance should be the same between the two routes. It is also recommended that you add the mishipeshu and/or kelpie encounters to help break up the day-to-day travel.
Growing River Corruption
As the players travel closer to the source of the river's corruption, the taint of the river's waters will become more severe. Once the players are roughly within 10 miles of the lake, you can apply the following effects to the river's waters:
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The water prevents creatures from adequately healing and causes them to become more susceptible to sickness. Any creature that is not undead or a demon and is submerged in the water has disadvantage on Constitution saving throws, medicine checks used on it have disadvantage, and if it receives healing, it only regains half the hit points it usually would.
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Creatures that are not undead or demons that consume the water must make a DC 14 Constitution saving throw or become diseased. Every 24 hours that elapse while diseased, the target must repeat the saving throw, reducing its hit point maximum by 3 (1d6) on a failure and curing the disease on a success. The target dies if the disease reduces its hit point maximum to 0. This reduction to the target's hit point maximum lasts until the disease is cured. If a creature succeeds on a saving throw against the disease, it is immune to its effects for the next 24 hours.
Navigating Reedymane River
Rate of Random Encounters: Every 4 Hours
Navigation DC: 15 to notice when they are near the lake
Foraging DC: 15 with disadvantage unless the purify food and water spell is used while foraging
Description: If the players take the longer, smoother route to the lake, the terrain will remain mostly the same. The most notable difference is the increase in felled trees and the presence of fester gnaws. If the players pass by the lake and continue upstream for more than 10 miles, the corruption and presence of the fester gnaws will quickly fade, indicating that they have traveled too far.
Adjusting the Difficulty
Easier Encounters.
- Change result 1 to 2 crocodiles, 1 hippos, or 2 jaguars
- Change result 2 to 1 giant crocodile, 1 hippopotamus gorgops, or 1 giant jaguars
- Change results 5-6 to 1 fester gnaw
- Change results 7-8 to 1 fester gnaw and 1 gunk spawn
Harder Encounters.
- Change result 1 to 6 crocodiles, 3 hippos, or 4 jaguars
- Change result 2 to 2 giant crocodiles, 2 hippopotamus gorgops, or 3 giant jaguars
- Change results 5-6 to 3 fester gnaws
- Change results 7-8 to 1 fester gnaw and 3 gunk spawn
*See Creatures section for all stat blocks
Navigating Timberland River (Rocky)
Rate of Random Encounters: Every 3 Hours
Navigation DC: 20 (Even if following river)
Foraging DC: 20 with disadvantage unless the purify food and water spell is used while foraging
Description: The rougher route to the lake allows players to reach their destination faster but poses many additional risks. Because the river flows through this terrain in the form of multiple branching streams, there is the possibility of hitting dead ends in small pools and ponds or taking sub-optimal routes that lengthen the journey. It will also be more difficult to bring a boat through this route as the streams may become too small for boat travel, and there are many more waterfalls.
If the players fail their navigation check, extend the length of their journey by a number of miles equal to twice the amount they failed it by. As long as they follow the streams upward, they won’t become truly lost. Still, the journey may take longer than they anticipated.
Adjusting the Difficulty
Easier Encounters.
- Change result 1 to 2 crocodiles, 1 hippos, or 2 jaguars
- Change result 2 to 1 giant crocodile, 1 hippopotamus gorgops, or 1 giant jaguars
- Change results 5-6 to 1 fester gnaw
- Change results 7-8 to 1 fester gnaw and 1 gunk spawn
Harder Encounters.
- Change result 1 to 6 crocodiles, 3 hippos, or 4 jaguars
- Change result 2 to 2 giant crocodiles, 2 hippopotamus gorgops, or 3 giant jaguars
- Change results 5-6 to 3 fester gnaws
- Change results 7-8 to 1 fester gnaw and 3 gunk spawn
*See Creatures section for all stat blocks
6. The Mishipeshu
This optional encounter can add more depth to the adventure and help break up the days of overland travel the players will be undertaking. It can be used if the players take the shortcut through the rough, rocky terrain. For background lore and a stat block for the mishipehsu, see pg.13.
Mishipeshus are fiendish and cruel, but they also have druidic ties and are dedicated to protecting their rivers. The mishipeshu's default response to intruders is to slay them ruthlessly. However, the recent corruption of the rivers has left it even more agitated and aggressive than usual. The mishipeshu's well-being is tied to its river, and the taint of its waters has left its mind addled. Unless it is actively trying to be stealthy, its confused thoughts will telepathically leak into the minds of other creatures within range.
Lead Up
Players with a passive Perception of 15 or higher will notice claw makes in the rock as they approach the mishipeshu's lair. Beyond that, it will not give any indication of its presence until it has decided to strike.
When the mishipeshu attacks, you can read the following description:
Mishipeshu Description
Emerging from its hiding place, a monstrous, cat-like creature attacks with a wild roar! It has aquatic features like scales, webbed feet, and a long razor spine running down its back. But it also possesses a dangerous set of horns with a metallic, copper-like gleam. The monster's eyes dart about with wild malice as it moves in for the kill.
The Mishipeshu's Attack
EXP Award: 4,800
The mishipeshu ruthlessly guards its waters and will not hesitate to attack intruders. It can command local water weirds to aid it, and it will use them to attack and distract the party while it stealthily approaches and attacks the party, targeting the most fragile players.
Start the fight with 2 water weirds attacking the players directly, grappling them, and keeping them distracted. One round later, the mishipeshu will appear on the scene, using stealth to attempt to move in and attack a fragile or isolated party member.
Bargaining with the Mishipeshu
The mishipeshu is cruel and hostile, but it also has the same problem the players do now. This will be revealed by its confused telepathy, which the players will detect as soon as it reveals itself. Players will hear thoughts coming from the mishipehsu, such as:
- ”River corrupters! I must guard these waters.”
- ”You will die along with the foul vermin!”
- ”The waters. . . .so foul. . . .can't think”
Mishipeshu Encounter Map
Legend
- F: Mishipeshu
- G: Water Wierd
- P: Player's Starting Area
If the players choose, they may attempt to persuade the mishipeshu to stop attacking them by convincing it they are here to save the river. Players who use an action to try to persuade the mishipeshu that they are here to slay the fester gnaws and purify the river may make a DC 15 Charisma (Persuasion) check to attempt to staff off the fiend’s wrath. Druids and rangers have advantage on this check.
If the check passes by 5 or more, the mishipeshu ceases its attack immediately. Otherwise, a success will stop it from attacking for one round, demanding why it should trust the players. During this time, the players can make another appeal to the mishipeshu. If the players attack it or its minions during this time, it will immediately resume its attack. To succeed on this second appeal, one of the characters will need to succeed on a DC 20 Charisma (Persuasion) check to calm the mishipeshu or a DC 20 Intelligence (Nature) check to explain what happened to the rivers and how they must be cleansed. Characters can bypass the need for this check if they provide the 5 gp worth of copper or some evidence that they have slain a fester gnaw.
Adjusting the Difficulty
Easier Encounters. Change the encounter to 1 mishipeshu. Change the EXP Award to 2,000.
Harder Encounters. Change the encounter to 1 mishipeshu and 4 water weirds. Change the EXP Award to 8,000.
Open Ended Interaction
The checks required to convince the mishipeshu to cease its attack are guidelines you can use for the interactions players may have with it if they attempt diplomacy. Be open to other means of persuasion the players utilize, which may make it easier (or harder) to soothe the fiend. The DCs provide guidelines for how difficult it should be to calm the mishipeshu, but the players may attempt other tactics that require different types of checks.
Aftermath
There are multiple possible outcomes from this encounter.
The Players Flee
In this case, the mishipeshu will continue to stalk them until they are within 5 miles of the lake. During this time, it will launch surprise attacks, fleeing if it drops below half health, only to return to stalk them later.
If the mishipeshu sees the party fighting fester gnaws or gunk spawns, it will instead join the fight to help them. At this point, it will be open to working with the party if they don’t attack it. See The Players Bargain With the Mishipeshu section below.
The Players Slay the Mishipeshu
In this case, the players can loot the following goods from its lair before moving on.
Loot Found In the Mishipeshu Lair
- 3,000 cp
- An engraved copper bowl worth 500gp
- potion of greater healing
- cloak of the manta ray
The Players Bargain with the Mishipeshu
If the players convince the mishipeshu that their goals are aligned, it will aid their journey. It dares not approach the source of the corruption for fear that it will lose its mind. Still, the mishipeshu will provide the players with clear directions on navigating the rocky terrain to reach the lake. This will result in players automatically passing all navigation checks to make their way through this terrain. Additionally, the mishipeshu will provide the players with the following items to aid them in their journey.
Gifts of the Mishipeshu
- potion of greater healing
- cloak of the manta ray
- elemental gem (Water)
7. The Kelpies
This optional encounter can add more depth to the adventure and help break up the days of overland travel the players will be undertaking. It can be used if the players take the longer route across the smoother terrain. For background lore and the stat block for kelpies, see pg.15.
The kelpies are more resilient to the river's corruption than other creatures. Their woes stem from the lack of travelers, resulting in a lack of food. Though they are not necessarily evil, the kelpies will see the players as a much-welcomed meal.
Lead Up
The shapeshifting kelpies give no indication of their true nature. Likewise, the terrain leading up to the encounter will not reveal anything particularly amiss besides the influence of the fester gnaws.
The Kelpies' Predation
EXP Award: 4,800
Two kelpies will assume the forms of sickly horses in need of help. When the players see them, you can read the following description.
Kelpie Initial Description
Two sickly-looking horses stagger along the river banks, gnawing at any healthy plants they can find. They looked alarmed at your presence but don't appear to have the energy to run and instead stagger about in desperation.
If none of the players touch them, they will attempt to use their charms to force them to do so. Once a kelpie has a player grappled, it will try to drag its target into the water to use its suffocating abilities. Kelpies with a target attached to them will move as deep into the water as possible to avoid interference from other players and make escape more difficult. The river here will be 30 feet deep. Kelpies will attempt to flee if they are dropped to one-quarter of their maximum health or lower.
Using Cold Iron Tacks
If the players have cold iron tacks, they can attempt
to force them upon the kelpies to bring them under
their control. The item description for the cold iron
tack describes how it can be used against the kelpies.
Adjusting the Difficulty
Easier Encounters. Change the encounter to
1 kelpie. Change the EXP Award to 2,000.
Harder Encounters. Change the encounter
to 3 kelpies. Change the EXP Award to 8,000.
Kelpie Encounter Map
Legend
- F: Fester Gnaw
- G: Chest
- P: Player's Starting Area
Aftermath
There are multiple possible outcomes from this encounter.
The Players Flee
If the players flee the encounter, the desperately hungry kelpies will stalk them and attempt another attack. They will secretly follow the players until they come within 10 miles of the lake. Since they are unlikely to get away with their shapeshifting tricks again, they will wait until they see a player doing an activity apart from the group, such as foraging or keeping watch while everyone else rests. They will then attempt to charm this player away from the group and towards the water, where they can drag their victim under.
The Players Defeat the Kelpies
If the players slay the kelpies or send them fleeing, they will have the opportunity to loot their hunting grounds. The shining glimmer of precious metals in the river will reveal the treasure left behind by past victims of the kelpies. If players dive into the waters to loot for treasure, they will find the following:
Treasure in the Kelpies' River
- 50 pp, 700 gp
- A ruby necklace worth 500 gp
- potion of greater healing
- necklace of adaptation
The Kelpies are Charmed
Kelpies charmed by the players using the cold iron tacks will serve as mounts for up to two medium-sized or four small-sized creatures each. They can aid the players in traversing the river waters, but they will fear the fester gnaws and their gunk spawn and not willingly attempt to attack or charm these creatures. They will also not voluntarily enter the dam of the fester gnaws.
8. Timberland Lake
This lake serves as the river's headwaters and holds the source of the river's corruption. The foul dam of the fester gnaws lies near the river's mouth, corrupting all the water that flows past it, and the players will have to cross the lake's waters to reach it. Because the lake is the epicenter of the river's corruption, players will constantly have to avoid or fight off fester gnaws and gunk spawns so long as they remain in the area.
If the players successfully reach the lake, award them 19,200 EXP. If you used the easier encounters from the random encounter tables, award 8,000 EXP, and if you used the harder encounters, award 32,000 EXP
Entering the Damned Dam
When the players reach the dam, read the following description.
Dam Description
Near the mouth of the river flowing out of the lake, you see a massive beaver dam constructed from corrupted wood, foul slime, and the occasional rotting corpse of a large woodland animal. The structure appears to extend beneath the water, which takes on a tainted hue as it flows past the structure.
If players try to attack the dam from the outside, all players within 5 ft. of it must succeed on a DC 15 Constitution saving throw or take 1d6 (3) necrotic damage for every festering wound they are suffering from and suffer one additional festering wound. Then read the following description:
Attack Against the Dam Description
The attack on the dam only served to unleash more of its vile corruption in a sickening spray of slime. Then, the dam's ooze flows into the damaged location in less time than it took you to damage it. A dark power from within the dam releases a pulse of energy, causing the ooze to rapidly repair the damage.
The players can enter the dam by swimming down 30 feet under the water to one of its two entrances. The entrances are on opposite sides of the dam.
9. Inside The Damned Dam
This section contains the adventure's climax, where the players face off against the fester gnaws and the source of their power, the gnawed effigy. Until they destroy the effigy, putting an end to the river's corruption is impossible.
Lead Up
There are always at least two fester gnaws* present inside the dam. However, the players can avoid alerting them by successfully sneaking up to the water's surface at the dam's entrance. From here, you can read the following description:
Dam Interior Description
The inside of the dam reeks of corruption. Near its center, etched into the floor with blood, is a large demonic symbol causing slight visual distortions in the air above it. The symbol lies before a large wooden effigy that appears to be the corpse of some sort of treant gnawed into a twisted and demonic form. The location where its face should be has been chewed away, and a new, twisted visage with glowing eyes hacked into its place.
The Dam Finally
EXP Award: 14,400
Once the players enter the dam from the water, the two fester gnaws will immediately attack. Within their dam, the fester gnaws can drop trees of any size they choose from the dam's ceiling if they are within 5 feet of a wall. Additionally, any fester gnaw can invoke their home's ambient magic to take lair actions. Only one fester gnaw can take a lair action per round. On initiative count 20 (losing initiative ties), any fester gnaw can take one lair action to cause one of the following effects:
Lair Actions
When fighting inside their dams, any fester gnaw can invoke their home's ambient magic to take lair actions. Only one fester gnaw can take a lair action per round. On initiative count 20 (losing initiative ties), any fester gnaw can take one lair action to cause one of the following effects:
-
Corrupted wooden spikes spring up to fill a 5-foot cube within 60 feet of the fester gnaw. Until initiative count 20 on the next round, the area is difficult terrain. During this time, creatures that enter the area for the first time or start their turn there take 3d4 piercing damage, and if the creature is not a demon, it gains a festering wound (see the fester gnaw stat block for the details of this effect).
-
Demonic energy spews out from a creature afflicted with any number of festering wounds. A creature within 60 feet of the fester gnaw takes 3 (1d6) necrotic damage for each festering wound afflicting it.
Fester Gnaw Dam Encounter Map
Legend
- F: Fester Gnaw
- E: Gnawed Effigy
- P: Possible Player's Starting Areas
The Gnawed Effigy
Two rounds of combat after the fighting begins, the gnawed effigy* comes to life. It will also immediately come to life if it is attacked directly. When it comes to life, read the following description, then roll for its initiative.
Gnawed Effigy Description
The effigy’s twisted face comes to life and lets loose a howl of rage and anguish. It trashes its limbs and stumbles forward, turning its gaze on all of you.
The gnawed effigy prioritizes affecting as many creatures as possible with its festering wounds. Besides this, it will prioritize hitting as many creatures as possible with its splinter burst and striking fragile targets with its skewer.
*See Creatures section for all stat blocks
Every round of combat, the gnawed effigy will emit a loud but low-pitched rumbling roar. It should be made clear to the players that it is calling out for other fester gnaws. Every 3 rounds that the gnawed effigy is active, a new fester gnaw will appear at a random dam entrance. Roll for its initiative at the start of that round.
Adjusting the Difficulty
Easier Encounters. Change the encounter to 1 fester gnaw and 2 gunk spawns when the party enters the dam. The gnawed effigy loses its legendary actions and has only one legendary resistance. Change the EXP Award to 2,000.
Harder Encounters. Change the encounter to 2 fester gnaws and 2 gunk spawns when the party enters the dam. Every 3 rounds, 1 gunk spawn and 1 fester gnaw enter the dam. Change the EXP Award to 24,000.
Aftermath
If the players flee from the fight, they will be pursued by the fester gnaws until they have left the lake area. The gnawed effigy will then restore all its hit points over the course of an hour.
If the players destroy the gnawed effigy, no more fester gnaws will appear at the dam. The existing fester gnaws in the dam may flee or fight to the end at your discretion.
Once the gnawed effigy is no more, the energies maintaining the dam will dissipate, causing the gunk holding the structure together to begin losing cohesion. 10 minutes after the fester effigy’s destruction, the dam will start collapsing, tree by tree.
Before this happens, players should be given a chance to loot the dam’s interior for the valuable items found there. Upon searching the dam, they will find the following:
The Dam Treasure
- 170 pp, 3,000 gp
- Blackened Remains of the Effigy worth 1,000 gp
- potion of greater healing
- staff of withering
Once the players have left the dam, you can move on to the final section.
10. Conclusion
With the dam destroyed and its remains drifting downstream, the river will slowly begin to heal. The remaining gunk spawns will dissolve over the next few days as there is no longer corrupted water to sustain them. The surviving fester gnaws will flee, and you can use some of the following ending options, depending on how far you want to draw out the adventure:
-
Done and Done. If you want the adventure entirely done at this point, the surviving fester gnaws will wither and die along with the gunk spawn.
-
Cathartic Cleanup. If you want one more immediate encounter, you can have the players hunt the last of the fleeing fester gnaws across the lake. Unlike before, you can have the fester gnaws behave more cowardly, giving the players a sense of satisfaction as they stamp out the demonic threat for good.
-
Showdown at Brookston. If you want one last significant encounter, you can have the surviving fester gnaws flee downstream towards the town in a desperate attempt to overrun it and use its buildings as source material for a new dam. The players can race downstream, trying to pick off as many as possible, before the chase ends in a final showdown at Brookston.
Future Adventures
If this adventure was a side quest for the players while they were on their way to a bigger adventure, they can now resume their primary quest. However, if you’d like this adventure to be a setup for a follow-up adventure, consider the following possibilities:
-
The wooden effigy was created by a corrupt sect of druids. A local druid approaches the players, asking for their help to stop their sinister brethren.
-
With the waters cleared, the local mishipeshu has grown more powerful. Now it blames the town for the recent events and has declared war on all its residents.
-
The water has been cleared of corruption, but the water horse population has been permanently affected, and they now maliciously hunt humanoids at every opportunity.
Adventure Resources
River Travel
Travel Activities
When traveling over great distances, rivers can be a boon for adventurers. They provide a consistent land feature that prevents travelers from becoming lost, are usually a source of plentiful food and drinkable water, and can be traveled by boat to reach distant locations quickly. However, they also present natural hazards and often attract dangerous predators.
Travel Activities
When the players travel long distances overland, rivers can play a large part in their journey. You may choose to modify the overland travel activities detailed in the Player's Handbook in the following ways when the players interact with a river.
Travel Pace
If the players are traveling by foot alongside a river, it has no significant impact on their travel pace unless the terrain becomes more difficult to navigate. If the players are traveling by boat, the direction and speed of the river affect their travel pace.
When traveling via paddleboat in still or gently flowing water, characters travel at a normal pace. If the current is stronger and they are going downstream, they can travel at a fast pace without suffering the normal drawbacks of doing so.
If they are traveling upstream against a strong current: they cannot travel at a fast pace, traveling at a normal pace results in suffering the drawbacks normally associated with traveling at a fast pace, and traveling at a slow pace does not provide its usual benefits.
Foraging
Another benefit afforded by rivers is that they usually provide ready access to food and fresh water. Unless the river is strangely devoid of life or polluted, it should generally be treated as though it provides an abundance of food and water sources for the purposes of harvesting.
River Hazards
Rapids
This is among the most common and dangerous river hazards. Beyond just consisting of fast currents, rapids often include a variety of hazards such as sharp rocks, foot entrapments, undercuts, and holes. Undercuts are locations where there is room for the water to flow, such as under a rock, but not for boats and creatures, leading to dangerous collisions.
Holes involve points in the river where the water's current flows over a rock and suddenly dives to the bottom of the river, pulling creatures and objects with it.
Boating
When traveling via boat through an area of intense rapids, the character paddling must make a Strength (Athletics) check to attempt to navigate it safely. If a group of characters is paddling, they make a group check. If one of the characters passes the check by 10 or more, the whole group automatically passes. If they fail, the boat slams into rocks and takes bludgeoning damage dependent on the intensity of the rapids, as shown in the Rapids and Obstructions table.
Crossing on Foot
If characters find themselves attempting to navigate rapids by foot, they must each make a Strength check to attempt to cross the waters safely. This check is made with disadvantage if the character is unable to stand in the water or has just been thrown into it. If a character fails this check, it is immediately pulled a number of feet downstream equal to the check's DC. If it collides with a rock or other hard object, the character takes the corresponding bludgeoning damage listed in the Rapids and Obstructions table. The character makes this check again at the start of each of its turns, getting pulled further downstream each time it fails.
Rapids and Obstructions
| Hazard DC | Bludgeoning Damage |
|---|---|
| 10 | 2d6 |
| 15 | 4d6 |
| 20 | 6d6 |
| 25 | 8d6 |
| 30 | 10d6 |
Waterfalls
When rapids result in a sudden plunge from a far enough height, they become a waterfall. The heights these drops can reach depend on the type of terrain the river is running through. The table below can be used to create a waterfall of a random height that suits a given terrain.
Waterfalls often present significant obstacles to characters traveling by river and can force them to take major detours or abandon their attempt at traveling by river entirely.
| Terrain Type | Waterfall Height |
|---|---|
| Low Hills | 1d4 x 10ft |
| Large Hills | 1d6 x 10ft |
| Highlands | 1d8 x 10ft |
| Small Mountains | 1d10 x 10ft |
| Mountainous Cliffs | 1d12 x 10ft |
Creatures
Crocodile
Large beast, unaligned
- Armor Class 13 (natural armor)
- Hit Points 37 (5d10 + 10)
- Speed 20 ft., swim 30 ft.
STR DEX CON INT WIS CHA 16 (+3) 12 (+1) 14 (+2) 3 (-4) 14 (+2) 5 (-3)
- Skills Perception +4, Stealth +3
- Senses darkvision 30 ft., passive Perception 14
- Languages ━
- Challenge 1 (200 XP) Proficiency Bonus +2
Hold Breath. The crocodile can hold its breath for 15 minutes.
Watery Lurker. The crocodile has advantage on Dexterity (Stealth) checks while submerged in water.
Actions
Bite. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 10 (2d6 + 3) piercing damage, and the target is grappled (escape DC 14). Until this grapple ends, the target is restrained, and the crocodile can't bite another target.
Death Roll. One creature the crocodile has grappled in the water must make a DC 14 Strength saving throw, taking 17 (4d6 + 3) piercing damage on a failed save or half as much damage on a successful one.
Fester Gnaw
Large fiend (demon), chaotic evil
- Armor Class 15 (natural armor)
- Hit Points 85 (10d10 + 30)
- Speed 30 ft., swim 30 ft.
STR DEX CON INT WIS CHA 16 (+3) 12 (+1) 16 (+3) 10 (+0) 14 (+2) 10 (+0)
- Skills Perception +4, Stealth +3
- Damage Resistances cold, fire, lightning
- Damage Immunities poison
- Condition Immunities poisoned
- Senses darkvision 120 ft., passive Perception 14
- Languages Abyssal, telepathy 120 ft.
- Challenge 4 (1,100 XP) Proficiency Bonus +2
Hold Breath. The fester gnaw can hold its breath for 20 minutes.
Keen Hearing. The fester gnaw has advantage on Wisdom (Perception) checks that rely on hearing.
Magic Resistance. The fester gnaw has advantage on saving throws against spells and other magical effects
Powerful Build. The fester gnaw counts as one size larger when determining its carrying capacity and the weight it can push, drag, or lift.
Wood Cutter. The fester gnaw's bite attack deals double damage to creatures, objects, and structures made of wood.
Actions
Multiattack. The fester gnaw makes two bite attacks. It can replace one of its bite attacks with a tail attack.
Bite. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 10 (2d6 + 3) slashing damage. If the target is a creature, it suffers a festering wound. A creature can have multiple festering wounds afflicting it at once. At the start of each of the wounded creature's turns, it makes a DC 14 Constitution saving throw, taking 3(1d6) necrotic damage per festering wound afflicting it on a failure, and ending all festering wounds afflicting it on a success. Alternatively, the wounded creature, or a creature within 5 feet of it, can use an action to make a DC 14 Wisdom (Medicine) check, ending the effect of all festering wounds afflicting it on a success. A creature that dies as a result of damage from a festering wound dissolves into a pile of rotting goo.
Tail. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 8 (1d10 + 3) bludgeoning damage. If the target is a creature, it must succeed on a DC 14 Strength saving throw or be knocked prone.
Giant Alligator
Large beast, unaligned
- Armor Class 14 (natural armor)
- Hit Points 67 (9d10 + 18)
- Speed 30 ft., swim 30 ft.
STR DEX CON INT WIS CHA 20 (+5) 10 (0) 14 (+2) 3 (-4) 14 (+2) 5 (-3)
- Skills Perception +4, Stealth +2
- Senses darkvision 30 ft., passive Perception 14
- Languages ━
- Challenge 3 (700 XP) Proficiency Bonus +2
Hold Breath. The alligator can hold its breath for 20 minutes.
Watery Lurker. The alligator has advantage on Dexterity (Stealth) checks while submerged in water.
Actions
Multiattack. The alligator makes two attacks: one with its bite and one with its tail. It can't make both attacks against the same target.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 16 (2d10 + 5) piercing damage, and the target is grappled (escape DC 16). Until this grapple ends, the target is restrained, and the alligator can't bite another target.
Tail. Melee Weapon Attack: +7 to hit, reach 10 ft., one target not grappled by the alligator. Hit: 9 (1d8 + 5) bludgeoning damage.
Death Roll. One creature the alligator has grappled in the water must make a DC 16 Strength saving throw, taking 32 (5d10 + 5) piercing damage on a failed save or half as much damage on a successful one.
Giant Crocodile
Huge beast, unaligned
- Armor Class 14 (natural armor)
- Hit Points 85 (9d12 + 27)
- Speed 20 ft., swim 40 ft.
STR DEX CON INT WIS CHA 22 (+6) 10 (+0) 17 (+3) 3 (-4) 14 (+2) 5 (-3)
- Skills Perception +5, Stealth +3
- Senses darkvision 30 ft., passive Perception 15
- Languages ━
- Challenge 5 (1,800 XP) Proficiency Bonus +3
Hold Breath. The crocodile can hold its breath for 15 minutes.
Watery Lurker. The crocodile has advantage on Dexterity (Stealth) checks while submerged in water.
Actions
Multiattack. The crocodile makes two attacks: one with its bite and one with its tail. It can't make both attacks against the same target.
Bite. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 22 (3d10 + 6) piercing damage, and the target is grappled (escape DC 17). Until this grapple ends, the target is restrained, and the crocodile can't bite another target.
Tail. Melee Weapon Attack: +9 to hit, reach 10 ft., one target not grappled by the crocodile. Hit: 15 (2d8 + 6) bludgeoning damage.
Death Roll. One creature the crocodile has grappled in the water must make a DC 17 Strength saving throw, taking 44 (7d10 + 6) piercing damage on a failed save or half as much damage on a successful one.
Giant Jaguar
Large beast, unaligned
- Armor Class 14 (natural armor)
- Hit Points 52 (7d10 + 14)
- Speed 40 ft., climb 30 ft., swim 20 ft.
STR DEX CON INT WIS CHA 18 (+4) 16 (+3) 15 (+2) 4 (-3) 14 (+2) 9 (-1)
- Skills Perception +4, Stealth +5
- Senses darkvision 60 ft., passive Perception 14
- Challenge 3 (700 XP) Proficiency Bonus +2
Ambusher. The jaguar has advantage on attack rolls against surprised creatures.
Keen Sight. The jaguar has advantage on Wisdom (Perception) checks that rely on sight.
Mask of the Jungle. The jaguar has advantage on Dexterity (Stealth) checks made to hide using foliage and may do so even if it is only lightly obscured while hiding this way.
Surprise Attack. If the jaguar hits a surprised creature with a bite attack during the first round of combat, the target takes an extra 13 (3d8) damage from the attack.
Actions
Multiattack. The jaguar makes two attacks: one with its bite and one with its claws. If both attacks hit the same target, the jaguar automatically grapples it (escape DC 14). Until this grapple ends, the jaguar can't attack another target.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 15 (2d10 + 4) piercing damage.
Claw. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 9 (1d10 + 4) slashing damage
Gnawed Effigy
Large fiend (demon), chaotic evil
- Armor Class 16 (natural armor)
- Hit Points 95 (10d10 + 40)
- Speed 30 ft.
STR DEX CON INT WIS CHA 20 (+5) 10 (+0) 18 (+4) 12 (+1) 14 (+2) 10 (+0)
- Damage Resistances bludgeoning, piercing
- Senses darkvision 120 ft., passive Perception 12
- Languages Abyssal, Common, Druidic, Elvish, Sylvan
- Challenge 8 (3,900 XP) Proficiency Bonus +3
Legendary Resistance (1/Day). If the gnawed effigy fails a saving throw, it can choose to succeed instead.
Unnatural Vitality. At the start of the gnawed effigy's turn, it regains 5 hit points for each creature within 100 feet of it that is suffering from a festering wound.
Actions
Befouled Skewer. Melee Weapon Attack: + 8 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) piercing damage. If the target is a creature, it suffers a festering wound. A creature can have multiple festering wounds afflicting it at once. At the start of each of the wounded creature's turns, it makes a DC 14 Constitution saving throw, taking 3(1d6) necrotic damage per festering wound afflicting it on a failure, and ending all festering wounds afflicting it on a success.
Alternatively, the wounded creature, or a creature within 5 feet of it, can use an action to make a DC 14 Wisdom (Medicine) check, ending the effect of all festering wounds afflicting it on a success. A creature that dies as a result of damage from a festering wound dissolves into a pile of rotting goo.
Splinter Burst. The gnawed effigy sprays wooden splinters at a point within 60 feet that it can see. Each creature within 10 feet of the point must make a DC 15 Dexterity saving throw. A creature takes 7 (3d4) piercing damage on a failed save and suffers a festering wound, or half as much damage with no additional effects on a success.
Legendary Actions
The gnawed effigy can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The gnawed effigy regains spent legendary actions at the start of its turn.
Move. The gnawed effigy moves up to its speed without provoking opportunity attacks.
Check. The gnawed effigy makes an ability check.
Skewer. The gnawed effigy makes an attack with its Befouled Skewer.
Reconstitute (Costs 3 Actions). If the gnawed effigy is suffering from one or more conditions that require it to make a saving throw to end, it may immediately make a save against each condition, ending the condition on a success. The only saving throws that this action can be used for are saves made at the end or the start of its next turn or using its action. It can use this action while incapacitated.
Gunk Spawn
Medium fiend (demon), chaotic evil
- Armor Class 12 (natural armor)
- Hit Points 68 (8d8 + 32)
- Speed 25 ft., swim 25 ft.
STR DEX CON INT WIS CHA 14 (+2) 10 (+0) 18 (+4) 6 (-2) 10 (+0) 6 (-2)
- Damage Vulnerabilities slashing
- Damage Immunities poison
- Condition Immunities poisoned, prone
- Senses darkvision 120 ft., passive Perception 10
- Challenge 1 (200 XP) Proficiency Bonus +2
Death Burst. When the gunk spawn dies, it explodes in a burst of corrupted ooze. Each creature within 10 feet of it must make a DC 14 Constitution saving throw, taking 1d6 necrotic damage for each festering wound it is suffering from on a failed save, and half as much damage on a pass.
Actions
Slam. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 7 (2d4 + 2) bludgeoning damage. If the target is a creature, it suffers a festering wound. A creature can have multiple festering wounds afflicting it at once. At the start of each of the wounded creature's turns, it makes a DC 14 Constitution saving throw, taking 3(1d6) necrotic damage per festering wound afflicting it on a failure, and ending all festering wounds afflicting it on a success. Alternatively, the wounded creature, or a creature within 5 feet of it, can use an action to make a DC 14 Wisdom (Medicine) check, ending the effect of all festering wounds afflicting it on a success. A creature that dies as a result of damage from a festering wound dissolves into a pile of rotting goo.
Sludge Breath (Recharge 6). The gunk spawn exhales a 15-foot cone of corrupted water. Each creature in that area must succeed on a DC 14 Dexterity saving throw, suffering two festering wounds on failed save, or one festering wound on a successful one.
Hippopotamus
Large beast, unaligned
- Armor Class 14 (natural Armor)
- Hit Points 76 (8d10 + 32)
- Speed 30 ft.
STR DEX CON INT WIS CHA 21 (+5) 8 (-1) 18 (+4) 4 (-3) 12 (+1) 7 (-2)
- Skills Intimidation +7
- Senses darkvision 30 ft., passive Perception 11
- Challenge 3 (700 XP) Proficiency Bonus +2
Blood Sweat. The hippopotamus has advantage on saving throws against disease.
Dense. The hippopotamus can move along the ground while underwater without having its movement speed reduced and does not suffer disadvantage on its bite attack while underwater.
Actions
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 18 (2d12 + 5) piercing damage.
Bonus Actions
Aggressive. The hippopotamus moves up to its speed toward a hostile creature that it can see.
Hippopotamus Gorgops
Huge beast, unaligned
- Armor Class 14 (natural armor)
- Hit Points 115 (10d12 + 50)
- Speed 40 ft.
STR DEX CON INT WIS CHA 23 (+6) 8 (-1) 20 (+5) 4 (-3) 12 (+1) 8 (-1)
- Skills Intimidation +9
- Senses darkvision 30 ft., passive Perception 11
- Challenge 5 (1,800 XP) Proficiency Bonus +3
Blood Sweat. The hippopotamus has advantage on saving throws against disease.
Dense. The hippopotamus can move along the ground while underwater without having its movement speed reduced and does not suffer disadvantage on its bite attack while underwater.
Actions
Bite. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 32 (4d12 + 6) piercing damage.
Bonus Actions
Aggressive. The hippopotamus moves up to its speed toward a hostile creature that it can see.
Jaguar
Medium beast, unaligned
- Armor Class 14 (natural armor)
- Hit Points 27 (5d8 + 5)
- Speed 40 ft., climb 30 ft., swim 20 ft.
STR DEX CON INT WIS CHA 17 (+3) 16 (+3) 13 (+1) 4 (-3) 14 (+2) 9 (-1)
- Skills Perception +4, Stealth +5
- Senses darkvision 60 ft., passive Perception 14
- Challenge 2 (450 XP) Proficiency Bonus +2
Ambusher. The jaguar has advantage on attack rolls against surprised creatures.
Keen Sight. The jaguar has advantage on Wisdom (Perception) checks that rely on sight.
Mask of the Jungle. The jaguar has advantage on Dexterity (Stealth) checks made to hide using foliage and may do so even if it is only lightly obscured while hiding this way.
Surprise Attack. If the jaguar hits a surprised creature with a bite attack during the first round of combat, the target takes an extra 7 (2d6) damage from the attack.
Actions
Multiattack. The jaguar makes two attacks: one with its bite and one with its claws. If both attacks hit the same target, the jaguar automatically grapples it (escape DC 13). Until this grapple ends, the jaguar can't attack another target.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) piercing damage.
Claw. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) slashing damage.
Kelpies. Kelpies are the most notorious and well-known of the water horses, as well as the female variant of these fey creatures. In their natural form, kelpies have long, reedy manes that drape across their pale, greenish complexions, and their eyes possess an eerily beautiful and haunting glow. When not in the water, kelpies drip with heavy mud, and their reeds weigh them down, preventing them from achieving the same level of land mobility as other horses. As such, they tend to stay closer to their homes than other water horses, preferring instead to lure creatures into their river domain.
Beguiling Predators. Kelpies prefer to prey upon lone, vulnerable targets, using their charms to separate an individual from nearby companions. They will then lure the victim out into the water, and once the isolated target touches the kelpie, it will quickly pull it to the bottom of its river home and well out of the reach of any help from its companions.
Charming Fey Steeds. River-dwelling fey prize kelpies as reliable and enchanting steeds, and especially powerful fey may have entire herds of kelpies at their command. They may even grant the services of these kelpies to those in their favor. This can result in some kelpies aiding noble heroes and serving as stalwart steeds in battles against other aquatic monstrosities.
Other kelpies are put to more sinister use. Hags enjoy utilizing kelpies to lure travelers into their clutches and will also employ kelpies in larger schemes, where they are used as spies. Hags will sometimes “gift” a kelpie disguised as a beautiful horse to someone. The kelpie then serves as a secret servant for the hag until the time comes to betray its would-be owner.
Kelpie
Large fey, chaotic neutral
- Armor Class 13
- Hit Points 82 (11d10 + 22)
- Speed 30 ft., swim 60 ft.
STR DEX CON INT WIS CHA 18 (+4) 16 (+3) 14 (+2) 10 (+0) 14 (+2) 18 (+4)
- Saving Throws Wis +5, Cha +7
- Skills Deception +7, Perception +5, Performance +7
- Senses darkvision 90 ft., passive Perception 15
- Languages Aquan, Sylvan
- Challenge 5 (1,800 XP) Proficiency Bonus +3
Amphibious. The kelpie can breathe air and water..
Charming Gaze. At the start of its turns, the kelpie can choose a creature it can see within 100 feet and force it to make a DC 15 Wisdom saving throw. On a failure, it becomes charmed and drops whatever it's holding. A creature charmed this way is incapacitated and spends each turn moving towards the kelpie by the most direct route available in an attempt to mount it. It doesn't avoid opportunity attacks but won't move into direct harm.
The target can repeat the saving throw at the end of each of its turns, and each time it takes damage, ending the effect on a success. The effect also ends if this ability is used to charm a different creature. A creature that breaks free of the charm is immune to this ability for the next 24 hours.
Actions
Hooves. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage.
Suffocating Grasp. Each creature grappled by the kelpie and submerged in water must make a DC 15 Constitution. On a failed save, a creature takes 31 (7d8) necrotic damage and starts to suffocate if it can't breathe water. On a pass, it takes half as much damage and does not begin suffocating.
Change Shape. The kelpie polymorphs into a large terrestrial beast or back into its true form. Its statistics are the same in each form. Any equipment it is wearing or carrying isn't transformed. It automatically reverts to its true form if it dies or is submerged in water.
Reactions
Adhere. When a large or smaller creature hits the kelpie with a melee attack or touches it, the kelpie can adhere that creature to itself, causing it to automatically become grappled by the kelpie (escape DC 15).
Mishipeshu
Medium fiend, neutral evil
- Armor Class 14 (natural armor)
- Hit Points 71 (13d8 + 13)
- Speed 40 ft., climb 30 ft., swim 40 ft.
STR DEX CON INT WIS CHA 17 (+3) 16 (+3) 13 (+1) 12 (+1) 16 (+3) 14 (+2)
- Saving Throws Dex +6, Cha +5
- Skills Perception +6, Stealth +6
- Damage Resistances acid, cold, lightning, thunder
- Senses darkvision 90 ft., passive Perception 16
- Languages Abyssal, Aquan, Druidic, Infernal, telepathy 60 ft.
- Challenge 5 (1,800 XP) Proficiency Bonus +3
Ambusher. The mishipeshu has advantage on attack rolls against surprised creatures.
Amphibious. The mishipeshu can breathe air and water.
Charge. If the mishipeshu moves at least 20 ft. straight toward a target and then hits it with a ram attack on the same turn, the target takes an extra 7 (2d6) damage. If the target is a creature, it must succeed on a DC 14 Strength saving throw or be knocked prone.
Keen Sight. The mishipeshu has advantage on Wisdom (Perception) checks that rely on sight.
Surprise Attack. If the mishipeshu hits a surprised creature with a bite attack during the first round of combat, the target takes an extra 9 (2d8) damage from the attack.
Actions
Multiattack. The mishipeshu makes three attacks: each one with a different weapon. If it hits the same target with a bite and claw attack, the mishipeshu automatically grapples it (escape DC 14). Until this grapple ends, the mishipeshu can't bite or claw another target.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 12 (2d8 + 3) piercing damage.
Claw. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) slashing damage.
Ram. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage.
Razer Tail. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 12 (2d8 + 3) slashing damage.
Mishipeshu. This monstrous creature appears to be a large, aquatic cat equipped with copper horns and a long razor-sharp fin capable of slicing through steel. Mishipeshu serve as the malevolent guardians of rivers and lakes, and though they are fiendish in nature, they work with druidic sects to protect the specific bodies of water they are bound to.
While they protect the sanctity of their watery homes, they do so with cruel brutality. Any creature that contaminates their waters in the slightest is subject to their terrible ire, and trespassers are often ambushed and torn to pieces without ever knowing what they did to incur the mishipeshu's wrath.
Adventure Maps
Animal Attack Encounter Map (With Grid)
Animal Attack Encounter Map (No Grid)
Fester Gnaw Encounter Map (With Grid)
Fester Gnaw Encounter Map (No Grid)
Gunk Spawn Encounter Map (With Grid)
Gunk Spawn Encounter Map (No Grid)
Mishipeshu Encounter Map (With Grid)
Mishipeshu Encounter Map (No Grid)
Kelpie Encounter Map (With Grid)
Kelpie Encounter Map (No Grid)
Fester Gnaw Dam Encounter Map (With Grid)
Fester Gnaw Dam Encounter Map (No Grid)
1.0.0 Changes
- Public Release
1.1.0 Changes
- Document clean up
1.1.1 Changes
- Replace mishipeshu art with placeholder
Referenced Documents
- Beavers 1.1.0
- Crocodilians 1.1.5
- Hippos 1.1.1
- Jaguars 1.2.2
- Mishipeshu 1.1.0
- Water Horses 1.2.0
- River Navigation 1.1.1