Bastard Sword, Variant (5e Equipment)
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Martial Melee Weapons
The middle ground between an arming sword and a longsword --sometimes called a "hand and a half sword"-- this blade's hilt is short enough to be used in one hand while also being long enough to warrant two hands if needed though it isn't as effective as a longsword.
While wielding this weapon in one hand, it has the finesse property. A character has proficiency with bastard swords if they have proficiency with either longswords or shortswords.