The Gunsmith
⌖This is an adaptation of and expansion upon a subclass from the original Artificer UA released in 2017. Adjustments have been made to allow the subclass to work with the Artificer as presented in Tasha's Cauldron of Everything, to bring it in line with other Specializations, and to solidify its identity as an aggressive damage-dealer.
To be honest, this subclass has become quite different from the original as it's been updated, so perhaps it's better to consider it "inspiration" rather than "adapation" at this point. Ultimately, the Gunsmith comes down not only to dealing large burst damage, but also doing so efficiently, and maximizing action economy as much as possible.
Artificer Specialist: Gunsmith
When you choose this specialization at 3rd level, you double down on your use of firearms, developing one of the deadliest ever created. You learn to not only create this powerful weapon, but to do so incredibly expediently, and to wield it with dangerous proficiency.
Tool Proficiency
When you adopt this specialization at 3rd level, you gain proficiency with smith's tools. If you already have this proficiency, you gain proficiency with one other type of artisan's tools of your choice.
Gunsmith Spells
You always have certain spells prepared after you reach particular levels in this class, as shown below. These spells count as artificer spells for you, but they don't count against the number of artificer spells you prepare.
| Artificer Level | Spells |
|---|---|
| 3rd | guiding bolt, hunter's mark |
| 5th | branding smite, scorching ray |
| 9th | conjure barrage, lightning arrow |
| 13th | sickening radiance, storm sphere |
| 17th | conjure volley, swift quiver 1 |
Thunder Cannon
At 3rd level, you forge a deadly firearm using a combination of arcane magic and your knowledge of engineering and metallurgy. This firearm is called a Thunder Cannon. It is a ferocious weapon which fires leaden slugs that can punch through armor with ease.
You are proficient with the Thunder Cannon. The firearm is a two-handed ranged weapon weighing 16 lb. that deals 2d6 piercing damage and has the ammunition and loading properties. Its normal range is 150 feet, and its maximum range is 500 feet. When you attack with your Thunder Cannon, you can use your Intelligence modifier, instead of Dexterity, for the attack and damage rolls. Finally, you can use your Thunder Cannon as your spellcasting focus.
If you lose your Thunder Cannon, you can create a new one over the course of two hours of strenuous activity using your smith's tools. If your Thunder Cannon is damaged, you can repair it in half that time. You can only have one Thunder Cannon at a time; if you create a new Thunder Cannon, your old one ceases to function.
Arcane Magazine
At 3rd level, you create a magical bag, case, quiver, or other worn container to store your Thunder Cannon ammunition. Your Arcane Magazine weighs 5 lb. and all ammo within it becomes weightless. A Gunsmith typically makes enough ammunition that they never run out, but in survival situations or extremely protracted battles of an hour or longer, they may find themselves running light. In such a situation, assume an Arcane Magazine can hold 400 rounds of ammunition, and that a Gunsmith can make 80 rounds over the course of a long rest, or 10 rounds over the course of a short rest, so long as they have access to their smith's tools for the duration.
Thunder Shot
Starting at 3rd level, once on each of your turns, you can declare before an attack that you are loading a Thunder Shot. You expend one spell slot to load a special piece of ammunition into your Thunder Cannon. The next time you deal damage with a shot from it on that turn, you deal extra thunder damage, in addition to the weapon's normal damage. The extra thunder damage is 2d8 for a 1st-level spell slot, plus 1d8 for each spell level higher than 1st, to a maximum of 6d8. In addition, the target must succeed on a Constitution saving throw against your spell save DC or be disoriented until the end of your next turn. While disoriented in this way, a creature has disadvantage on Wisdom (Perception) checks and Dexterity saving throws, and attacks against them have advantage. If you load a Thunder Shot but do not hit with a ranged attack made with your Thunder Cannon that turn, you automatically recall the magic within the shot at the end of your turn, regaining the spent spell slot.
Double Shot
Starting at 5th level, you add a second barrel, loading mechanism, or other similar component to your Thunder Cannon, allowing you to attack twice, rather than once, whenever you take the Attack action on your turn and use your Thunder Cannon for both of the attacks. The Thunder Cannon still has the loading property, but allows for up to two attacks per turn, rather than the usual one.
Modular Design
Starting at 9th level, you create specialized modifications for your Thunder Cannon, as described below. Each modification weighs 5 lb. and requires 30 minutes of strenuous activity using your smith's tools to create. You can add or remove a modification as an action. Beginning at 17th level, you can have two modifications on your Thunder Cannon at a time. Use your artificer spell save DC for the attachments' effects.
Adaptable Grip. You affix a stock to your Thunder Cannon which you can quickly fold or unfold. Being within 5 feet of a creature doesn't impose disadvantage on your ranged attack rolls with your Thunder Cannon. As a reaction, when a creature would normally provoke an attack of opportunity from you, you can make a ranged attack with your Thunder Cannon against that creature.
Bulwark Guard. You affix a shield to the front of your Thunder Cannon, with space to accommodate your aiming. While in combat, you have half-cover from the direction you're facing, which you choose on each of your turns. As a reaction when a ranged attack is made against you, you can turn to face the attack's point of origin before it hits, granting the benefits of half-cover against the triggering attack.
Crushing Axe. You affix a heavy axe-like blade to the end of your Thunder Cannon. In addition to its normal properties, your Thunder Cannon counts as simple melee weapon with which you are proficient. It deals 1d10 slashing damage on a hit, and as a reaction when you hit with it using the axe, you can force the target of the triggering attack to make a Strength saving throw. On a failure, the target is pushed 5 feet away and knocked prone.
Elemental Infuser. You affix a strange device to your Thunder Cannon which infuses your shots with elemental power. Attacks from your Thunder Cannon deal extra damage equal to your proficiency bonus. The type of damage is acid, cold, fire, lightning, necrotic or radiant (you choose at the start of each of your turns). As a reaction when you hit with an attack with your Thunder Cannon, you can detonate the round. Every creature within 5 feet of the target of the triggering attack must succeed on a Dexterity saving throw or take damage as though hit by the triggering shot.
Forceful Bayonet. You affix a pointed blade to the end of your Thunder Cannon. In addition to its normal properties, your Thunder Cannon counts as a simple melee weapon with which you are proficient. It deals 1d10 piercing damage on a hit, and as a reaction when you hit with it using the bayonet, you can force the target of the triggering attack to make a Strength saving throw. On a failure, the target is pushed up to 15 feet away.
Precision Sight. You affix a scope to your Thunder Cannon. When you attack with your Thunder Cannon, you score a critical hit on a roll of 19 or 20 on the d20. As a reaction, when you hit with an attack with your Thunder Cannon, you can re-roll the attack, potentially turning it into a critical hit (but never turning it into a miss).
Thunder Blaster
Starting at 15th level, you reach the apex of your mastery as a Gunsmith and apply your final, and greatest, upgrade to your thunder cannon: the Thunder Blaster, which can infuse your rounds with certain effects. As a bonus action, you infuse a round with a Blast chosen from the list below. When you choose a blast, you may choose to make the blast cause thunder damage, instead of the listed type. The next time you take the Attack action with your Thunder Blaster this turn, you replace one of the attacks with the chosen Blast. You can use this ability a number of times equal to your proficiency bonus, regaining all expended uses upon completion of a short rest.
Force Blast. When you fire this blast, rather than making an attack roll, you fire a wide blast of blunt force in a 30-foot cone in front of you. Each creature in that area must make a Dexterity saving throw against your spell save DC, taking 4d6 force damage on a failed saving throw, or half as much on a success.
Inferno Blast. When you fire this blast, rather than making an attack roll, you launch an explosive round from the gun at a point within the gun's normal range. The round detonates in a 20-foot radius sphere from its point of impact. Each creature in that area must make a Dexterity saving throw against your spell save DC, taking 4d6 fire damage on a failed saving throw, or half as much on a success.
Storm Blast. When you fire this blast, rather than making an attack roll, you cause the gun to unleash a bolt of lightning, 5 feet wide and 60 feet long. Each creature in that area must make a Dexterity saving throw against your spell save DC, taking 4d6 lightning damage on a failed saving throw, or half as much on a success.
Art Credit
Adam Nichols art from Hellboy: the Science of Evil
© Konami 2004
Dark Heresy 2E Handbook
© Games Workshop 2008
Artstation - ji zhang https://www.artstation.com/artwork/DxzvbA
Artstation - Wardog Studios https://www.artstation.com/artwork/PoB9w8
Deviantart - TsimmerS https://www.deviantart.com/tsimmers/art/Gun-Sk-610909320