Elven Lightblade (5e Equipment)
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Martial Melee Weapons
The elven lightblade has the weight and and finesse of a dagger, but the length and strength of a shortsword. Its thin, flexible blade slips easily into the seams of armor, or between the ribs of an enemy. In elven cultures, a decorated lightblade is often used as a badge of office.
You are proficient with elven lightblades if you have the Elven Weapon Training racial feature, or the Elven Blade Master feat.