Chainsaw Bayonet (5e Equipment)
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Martial Melee Weapons
It's a bayonet you can attach to a rifle! It's also a chainsaw!
You can use your action to fix a chainsaw bayonet to a rifle. While wielding a rifle to which the bayonet is attached with both hands, you can engage in two-weapon fighting as if you were wielding the rifle in one hand, and a light weapon that deals 1d10 slashing damage in your off hand. You have disadvantage on attack rolls with a chainsaw bayonet that has not been fixed to a rifle, as its not intended to be used alone.