Sword of Life Stealing
Weapon,
Rare
(requires attunement; cost 2000 gp)
Crafting Components
Vampire dust
When you use this weapon to make an attack against a creature that is not a construct or undead and roll a natural 20, the creature takes an extra 3d6 necrotic damage and you gain an amount of temporary hit points equal to the necrotic damage dealt.
Source