You pull the magical energy from an undead creature and use it to boost your own health. 

When you cast this spell, you can choose whether it affects a 40-foot cone extending from yourself, a 20-foot diameter sphere centered on yourself, or a single target within range. 

If you choose to affect an area with this spell, every creature in the area of effect must make a Charisma saving throw against your spell save DC. On a failure, they lose 14 (4d6) hit points. This loss of hit points cannot be reduced or negated in any way. You regain hit points equal to half of the combined damage dealt to all creatures in the area.

If you choose to affect a single target within 60 feet, they must succeed on a Charisma saving throw or lose 28 (8d6) hit points. This loss of hit points cannot be negated or reduced in any way. You regain hit points equal to the amount of hit points the target lost.

Undead creatures you've created have disadvantage on this saving throw. They can choose to fail, if commanded.

You can only learn this spell or add it to your spellbook if you know the animate dead, false life, and ray of enfeeblement spells.

At higher levels. For every level above 3rd that this spell is cast, increase the damage of the area affect by 1d6 and the single target by 2d6.