Versatility (5e Feat)
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You have learned how to wield weapons more powerfully than most warriors do, and your strikes can show it.
If a weapon does not have the Two-Handed, Versatile, or Light properties, is melee, and has a damage die lower than 2d6 or 1d12, you may treat it as a Versatile weapon, increasing the die size by 1.
For example, the Rapier is 1d8, finesse, but not versatile. If you wield it in two hands with this feat, it would deal 1d10 damage.