Glass Cannon

The Glass Canon subclass allows you to deal massive amounts of damage in a single turn in exchange for a downtime in which you become ineffective in combat.

Glass Cannon

Beginning at 3rd level you gain access to the Artificer's Glass Cannon.
Once per day, as an action you may use your Glass Cannon to decimate your enemies.
Make a ranged attack against a creature within 180 ft., using your firearm of choice, this attack deals 16d8 piercing damage. After firing the Glass Cannon, your firearm overheats and needs to cool down for it's max recharge duration.
This feature may only be used once per day.

Arcane Artillery Mods

Beginning at 5th level, you gain access to powerful modifications to your Arcane Artilleries.
At the beginning of each day you may pick a combination of modifications to manifest for the remainder of the day. You may attach a modification to your Arcane Artillery as a bonus action. This lasts until the end of your turn. You have a number of modifications equal to your proficiency modifier. You create new modifications upon taking a long rest.

Burst Cannon

Your Arcane Artillery fires a burst of shells in a 15 ft. cone dealing your Artillery's damage as bludgeoning damage. You make individual rolls for each target.

Piercing Shot

Your Arcane Artillery fires a penetrating round that pierces through your foes. This shot bypasses any resistance to piercing damage. You make individual rolls for each target.

Arcane Impact

At 9th level you empower your Glass Cannon further with arcane energy allowing it to fire with greater force. Increase your Glass Cannon damage die by one step. (d8 -> d10)
At 15th level the damage increases to d12.

Elemental Cannon

At 15th level you have mastered augmenting the Glass Cannon with new modifications.
At the beginning of each day you may select one of the modifications listed below as your Elemental Augmentation.

Conflagration: Your Glass Cannon begins to radiate with scalding heat and launches scorching napalm. Enemies within 20ft. of the blast must make a Dexterity Saving throw or take 18d12 fire damage (half on success), leaving an inferno of flames raging 20 feet from the point of impact. Enemies entering the area, beginning their turn in the area, or ending their turn in the area take 4d8 fire damage.
Glacial Divide: Your Glass Cannon drops the temperature around it and fires a chilling beam of energy. Enemies within the range of the beam must make a Dexterity Saving throw or take dealing 18d12 cold damage (half on success), leaving a 10 foot tall wall in the path of the beam. All creatures caught in the path are restrained. They may make a Strength saving throw against your Spell Save DC to break free leaving a gap in the wall equal to their size.
Magnetic Railgun: Your Glass Cannon begins to thrum with electrical force and fires a beam of lightning in a line. Enemies within the range of the beam make a Dexterity Saving throw or take 18d12 lightning damage. This beam leaves behind a magnetic field that pulls all creatures within 20 feet towards the line taking 4d6 force damage. Creatures that impact each other on the line are stunned until the end of your next turn.
Noxious Cloud: Your Glass Cannon fires a canister infused with arcane magic, when the canister lands it sprays a noxious green cloud. All creatures within 20 foot radius must make a Constitution Saving throw or take 18d12 acid damage. Each creature that enters the area for the first time or begins their turn in the area must succeed a Constitution saving throw or take 4d8 poison damage and the Poisoned condition.
Shroud of Darkness: Your Glass Cannon becomes shrouded in darkness and fires a 15 foot wide ray of shadow. Enemies within the center of the beam must make a Dexterity Saving throw or take 18d12 necrotic damage (half on success). Allies hit by the beam receive half the damage rolled as temporary HP.
Arcane Fission: Your Glass Cannon fires a supercharged meteorite shard at a creature within 100 feet dealing 9d12 piercing damage. The shard will explode after 1d4 turns. A creature may use it's action to attempt to remove the shard. It must succeed an Athletics (Strength) or Arcana (Intelligence) check against your Spell Save DC. On a failure the charge detonates, on a success they are able to disarm the shard.

The shard deals twice the initial damage as force damage to the attached creature upon detonation. Creatures within 10 feet must make a Dexterity Saving throw or take 9d12 force damage.