Tier 1 Epic necromancy

Casting Time: 1 action
Range: 60 feet
Components: V, S, M (a handful of earth taken from a dead world)
Duration: Instantaneous

Your touch infects a creature with a dangerous infusion with the essence of death. Make a single melee spell attack against a creature within range. On a successful hit, the target becomes wreathed in negative energy for 1 minute. When a target so wreathed would regain hit points, the negative energy prevents the creature from regaining those hit points and it instead loses that many hit points. Once the spell prevents a target from regaining 200 hit points in this manner, the effect ends.

At Higher Levels. When you cast this spell as a tier 2 Epic spell or higher, the amount of hit points the spell can prevent the target from regaining increases by 100 per tier above tier 1.

Ref: ELCR p92