Vampiric Life Theft

This spell represents the Life Theft property of one of the Daggers of Life Stealing. The vampiric hunger bound within the fang awakens when the blade finds a perfect opening.

When you roll a 20 on the d20 for an attack roll made with the dagger, if the target is neither a Construct nor an Undead, it takes an extra 1d12 + 3 necrotic damage. You gain temporary hit points equal to the necrotic damage actually dealt by this property.