Spellcasting. The Artifact Researcher is a 5th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 14, +6 to hit with spell attacks). The Artifact Researcher has the following Artificer spells prepared:

Cantrips (at will): Mending, Fire Bolt.

1st level (4 slots): Absorb Elements, Catapult, Faerie Fire, Shield, Thunderwave

2nd level (2 slots): Heat Metal, Invisibility, Scorching Ray, Shatter.

Eldritch Flamethrower. The Artifact Researcher is always accompanied by mobile cannon. It is a Small Magical Construct. It has an AC of 18 and 25 hit points. It is immune to poison damage, psychic damage, and all conditions. 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. If it is reduced to 0 hit points, it explodes, leaving nothing behind but tiny shards.

On its turn, and while within 60 feet of the cannon, the Artifact Researcher can use its bonus action to move the cannon 15 feet and use its attack action. The cannon then exhales fire in a 15-foot cone from itself. Each creature in that area must make a DC 14 Dexterity saving throw, 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.

Arcane Firearm. The Artifact Researcher uses a curved wand-like device with a hole at its end as an arcane focus. It is carved with a sequence of personal arcane sigils. When the Artifact Researcher casts a damaging spell through the firearm, it can add a d8 to the damage roll of the spell (already included in firebolt).

Arcane Fire Bolt. Ranged Spell Attack: +6 to hit, range 120 ft., one target. Hit: 16 (2d10 + 1d8) fire damage.