Credit: Ideas & Images from Dale Kellegrew's Artificer (slightly altered by me). Purchase: DMs'guild Link.
Artillerist
An Artillerist specializes in using magic to hurl energy, projectiles, and explosions on a battlefield. This destructive power is valued by armies in the wars on many different worlds. And when war passes, some members of this specialization seek to build a more peaceful world by using their powers to fight the resurgence of strife. The world-hopping gnome artificer Vi has been especially vocal about making things right: "It's about time we fixed things instead of blowing them all to hell."
Level 3: Tool Proficiency
When you adopt this specialization you gain proficiency with woodcarver's tools. If you already have this proficiency, you gain proficiency with one other type of artisan's tools of your choice.
Level 3: Artillerist Spells
You always have certain spells prepared after you reach particular levels in this class, as shown in the Artillerist Spells table. These spells count as artificer spells for you, but they don’t count against the number of artificer spells you prepare.
Artificer Level Artillerist Spells
3rd Magic Missile, Thunderwave
5th Scorching Ray, Shatter
9th Fireball, Wind Wall
13th Ice Storm, Wall of Fire
17th Cone of Cold, Wall of Force
Level 3: Cannon
You've learned how to create a magical cannon. Using woodcarver's tools or smith's tools, you can take an action to magically create a Small or Tiny Cannon in an unoccupied space on a horizontal surface within 5 feet of you. A Small Cannon occupies its space, and a Tiny one can be held in one hand. Once you create a Cannon, you can't do so again until you finish a long rest or until you expend a spell slot or Magical Tinkering use to create one. You can have only one Cannon at a time and can't create one while your cannon is present.
The cannon is a magical object. Regardless of size, the cannon has an AC of 18 and a number of hit points equal to five times your artificer level. It is immune to poison damage and psychic damage. If it is forced to make an ability check or a saving throw, treat all its ability scores as 10 (+0). If the mending spell is cast on it, it regains 2d6 hit points. It disappears if it is reduced to 0 hit points or after 1 hour. You can dismiss it early as an action.
When you create the cannon, you determine its appearance and whether it has legs. You also decide which type it is, choosing from the options on the Eldritch Cannons table. On each of your turns, you can take a bonus action to cause the cannon to activate if you are within 60 feet of it. As part of the same bonus action, you can direct the cannon to walk or climb up to 15 feet to an unoccupied space, provided it has legs.
| Canon | Activation |
| Flamethrower | The cannon exhales fire in an adjacent 15-foot cone that you designate. Each creature in that area must make a Dexterity saving throw against your spell save DC, taking 2d8 fire damage on a failed save or half as much damage on a successful one. The fire ignites any flammable objects in the area that aren't being worn or carried. |
| Force Cannon | Make a ranged spell attack, originating from the cannon, at one creature or object within 120 feet of it. On a hit, the target takes 2d8 force damage, and if the target is a creature, it is pushed up to 5 feet away from the cannon. |
| Protecting Core | The cannon emits a burst of positive energy that grants itself and each creature of your choice within 10 feet of it a number of temporary hit points equal to 1d8 + your Intelligence modifier (minimum of +1) |
Level 5: Enhanced Firearm
You know how to create a conduit for your destructive spells. When you finish a long rest, you can use woodcarver's or smith's tools to enhance a spell focus, and thereby turn it into your Enhanced Firearm. You can maintain only one Enhanced Firearm at a time, but you can do so indefinitely. You can use your Enhanced Firearm as a spellcasting focus for your Artificer spells. When you cast an Artificer spell through the firearm, roll a d8, and you gain a bonus to one of the spell's damage rolls equal to the number rolled.
Level 9: Explosive Cannon
Every Cannon you create is more powerful:
- The cannon's damage rolls all increase by 1d8
- The Protector's protective die increases to a d12 instead of a d8.
- As an action, you can command the cannon to detonate if you are within 60 feet of it. Doing so destroys the cannon and forces each creature within 20 feet of it to make a Dexterity saving throw against your spell save DC, taking 5d8 force damage on a failed save or half as much damage on a successful one
Level 15: Perfected Armor
You’re a master at forming well-defended emplacements using Arcane Cannons:
- You and your allies have half cover while within 10 feet of your Cannon, as a result of a shimmering field of magical protection that the Cannon emits.
- You can now activate two cannons at the same time with one bonus action.
- You can now detonate two cannons at the same time with one action.**
- You can create two cannons with the same action (you must still use a magical tinkering or spell slot use per cannon to recreate them).