Berserker’s Prosthetic Arm (5e Equipment)
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Wondrous item, rare (requires attunement)
Due to their reckless nature, it’s not uncommon for berserkers to loose a limb. This can be debilitating, especially in worlds without magic. Certain skilled craftsman have devised ways to forge replacement arms with magnetic fingers, enabling injured warriors to fight on.
Metal, and Nothing More: You have disadvantage on attack rolls while wielding weapons not made of metal with this arm as it is magnetic. Your unarmed strikes with this arm deal 1d6 + your Strength modifier bludgeoning damage.
Cannon: As a bonus action, you can drop this arm’s wrist. You can not do this while holding an item in it. After doing this, as an action, you can fire a small cannon ball out of the exposed wrist. The first creature in a 60ft line must succeed on a DC 16 Dexterity saving throw. A creature takes 10d6 bludgeoning damage on a failed save, and takes half as much on a successful one. Each creature in a 15ft cone in the same direction must also make a DC 14 Dexterity saving throw. A creature takes 4d8 fire damage on a failed save, and takes half as much on a successful one. When you use this property of the prosthetic arm, you must spend your entire movement speed for the turn or be forced 15ft back. If you are pushed back, and there is a wall in the way, you take 2d6 bludgeoning damage. Each use of the cannon costs 50 gp of blasting powder/gunpowder and use of a 15 gp small cannonball that can be reused.
If you attempt to use the cannon more than twice in a single day, you must roll a d20 for each additional time you fire it. On a roll of 1-9, the prosthetic arm breaks. On a 10-18, your shoulder that houses the prosthetic arm dislocates, and you must spend an action and succeed a DC 13 Strength (Athletics) check to regain use of your arm. On a 19-20, nothing happens.