Nine Lives Stealer Longsword

Weapon Versatile Very Rare (this item requires attunement)

You gain a +2 bonus to attack and damage rolls made with this magic
weapon. The sword has 1d8 + 1 charges. If you score a critical hit against a creature
that has fewer than 100 hit points, it must succeed on a DC 15 Constitution
saving throw or be slain instantly as the sword tears its life force from its
body (a construct or an undead is immune). The sword loses 1 charge if the
creature is slain. When the sword has no charges remaining, it loses this
property. Versatile. This weapon can be used with one or two hands. A damage value
in parentheses appears with the property—the damage when the weapon
is used with two hands to make a melee attack. Found On: Magic Item Table H Source: DMG, page 183. Available in the SRD.