Through heavy modification of a prosthetic, you were able to put 5 types of guns into your mechanical body. You can switch between modes as a bonus action. You have a pool of bullets inside your prosthetics that your guns use. Each gun pulls from this bullet pool, but with different costs. You can use a number of bullets equal to your proficiency modifier per turn. Instead of putting your bullets in the gun, you insert them into your prosthetic. You can hold 50 bullets in your body at a time. If ANY guns misfires, the entire arm breaks and you must spend an action to repair it (the arm is broken in the meantime); if you fail the repair, you must use 250 gp worth of materials to repair it.
Because of the nature of the mechanics, you can "draw" and "stow" these weapons as a free action.
Each firearm has a special firing mode attacked to it, detailed on the attached actions.
1st level: Pistol: 1d8 M:1 piercing (50/100) Cost: 1
7th level: Rifle: 2d8 M:2 piercing (200/600) Cost: 3
10th level: Shotgun: 3d6 piercing M:5 (Cone 15/30) cost: 2
15th level: Mortar: 3d6 fire 15ft radius M:5 (30/75) cost: 4
18th level: Railgun: 4d6 piercing line M:5 (100/200) cost: 6
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