Bayonet (5e Equipment)
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Simple Melee Weapons
A bayonet (from French baïonnette) is a knife, sword, or spike-shaped weapon designed to fit in, on, over, or underneath the muzzle of a rifle, musket, or similar two-handed firearm. In this regard, it is an ancillary close-quarter combat or last-resort weapon.
Plug bayonets (1 gp) are the earliest form of this weapon. While attached, the firearm cannot be used to make a ranged attack.
Ring or socket bayonets (2 gp) were later developments that still allow the weapon to be fired.
If the bayonet is used when not attached to a two-handed firearm, it is considered an improvised weapon.