Artwork provided by Wizards of the Coast (Fan-use)
Simon Dominic did the original artwork, and absolutely killed it.
Toxrill the Corrosive
Slime, eat, repeat.
Spiciness: 4.5/5
AOE crowd control can sometimes shut down a whole party, which puts this in the "Boss Fight" category, but the lack of AoE damage makes a TPK less likely. Definitely a threat to melee attackers!
Preparation
The Slimed Condition
For each stack of slimed that a creature has, it suffers the following effects:
- The creature has a -1 penalty to their Proficiency Bonus as the slime entangles them (min 0)
- The creature's movement speed is reduced by half their normal movement speed.
- At the beginning of a slimed creature's turn, it takes 1d6 acid damage per stack of Slimed on it.
- A creature who dies while Slimed begins to have their corpse transformed. At the start of each of their turns, roll a d4 per stack of slimed on them. If the result is 8 or higher, they become a Toxrill Slug, are friendly to Toxrill, and hostile to the party. The corpse is consumed during this process.
Slime Stack Removal. The Slime is flammable, and any amount of fire damage applied to the creature will deal an additional d4 per stack of slimed, removing all stacks at once. Alternatively, the slime can be dissolved in water, removing 1 stack per round. Additionally, effects such as Prestidigitation or Purify Food & Drink that can clean some amount of liquid will remove a number of stacks equal to the spell's level (min 1). Let your players be creative and have fun with it! The slime is not, however, a disease or poison so those effects don't work.
In other words, a creature with a proficiency bonus of 3 and movement speed of 30 would, upon having 2 stacks of Slimed, have a proficiency bonus of 1, a movement speed of 0, and take 2d6 acid damage at the start of its turn.
Note: A downed player is still slimed, so they automatically fail 1 death save each turn, though they also roll a death save so its possible they fail 2. This really pressures the players into spending their actions picking up players!
Cooking the Toxrill Slugs
Round 1+: These slugs are more thematic than actually useful, but may help trigger failed death saves. As their speed is only 10, they can't really chase prey and will prioritize targets that can't run away-- the slimed & the fallen.
Cooking the Toxrill
While flavorful and strong, the Toxrill is not particularly hard to run, mostly because it's a dumb slug. Would be weird for it to start using advanced tactics in its attack pattern!
Don't forget the slime! Remember that, once per turn, any contact with Toxrill triggers a slime stack (on failed dex save). This means if a player does a melee attack, if Toxrill hits them with its attacks (including attacks of opportunity), or if they touch it in any way (moving through its space, grappling it, trying to ride it-- depends on how adventurous your party gets). It's only once per turn, but there's plenty of ways that you can dish out extra slime stacks on EVERY turn!
On Toxrill's turn. Try to get in range of as many players as possible-- you're looking to maximize the amount of slime your Slime Coat can do. If one of these players is slimed, feast them-- otherwise, Shell Slam!
Legendary Actions. You can immediately Slime Coat after your turn if you expect the players you've gotten in range of to run away, but if you think players might run towards you, wait until they do to maximize its effect. Its likely they'll spread out after you do this once, so make sure the first time catches them off guard! If you do wait, consider doing a Shell Slam instead to knock someone prone. If you do and they get slimed (reducing their speed to 15ft), standing up would require 7.5 ft of movement, meaning they literally can't get out of the reach of Slime Coat (10ft).
Toxrill
Large aberration, chaotic evil
- Armor Class 17 (natural armor)
- Hit Points 135 (18d10 + 36)
- Speed 30 ft.
STR DEX CON INT WIS CHA 21 (+5) 9 (-1) 15 (+2) 4 (-3) 12 (+1) 8 (-1)
- Saving Throws Con +6, Int +1, Wis +5
- Senses darkvision 120 ft., passive Perception 20
- Damage Resistances. Fire, Poison, Necrotic
- Damage Vulnerability Cold, Lightning
- Challenge 10 (5,900 XP) Proficiency Bonus +4
Mucous Membrane. The Toxrill coats anything that touches it in a corrosive slime. Once per turn, when a creature would make a melee attack against Toxrill, Toxrill would deal melee damage to them, or they would touch Toxrill in any way, that creature must make a Dexterity Save (DC 15) or gain a stack of Slimed. If they are grappling Toxrill, they automatically fail this save.
Actions
Feast. Toxrill begins to feed on a creature who is prone and Slimed. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 15 (3d6 + 5) piercing damage, and Toxrill is healed for half the damage done.
Shell Slam. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 15 (3d6 + 5) piercing damage, and the target is knocked prone.
Legendary Actions
The Toxrill can take legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. The Toxrill regains spent legendary actions at the start of its turn.
- Shell Slam. The Toxrill makes one Shell Slam.
- Slime Coat. Each creature within 10ft of Toxrill must make a Dexterity Save (DC 15). On a failure, they gain one stack of Slimed.
Toxrill Slug
Tiny monstrosity, unaligned
- Armor Class 13 (natural armor)
- Hit Points 22 (4d4 + 12)
- Speed 10 ft.
STR DEX CON INT WIS CHA 11 (+0) 14 (+2) 17 (+3) 5 (-3) 13 (+1) 4 (-3)
- Skills Perception +3
- Senses darkvision 60 ft., passive Perception 13
- Languages —
- Challenge 1/4 (50 XP) Proficiency Bonus +2
Regeneration. The pest regains 5 hit points at the start of its turn if it has at least 1 hit point. If it takes fire damage, this trait doesn't function at the start of the pest's next turn.
Actions
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) piercing damage.
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