Drain Intellect

Make a melee spell attack against a creature you can reach. On a hit, the target takes 3d10 psychic damage and makes an intelligence saving through against your spell save dc. On a failed save, the creature's int score is reduced by 1 and you are healed for 1d10 + your warlock level and experience a euphoria that lasts for 10 minutes. The stat reduction lasts until the target is healed by a greater restoration or more powerful healing magic. On a successful save, the target's stats are not lowered and the caster receives no healing.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d10 for each slot level above 3rd, and the healing from a failed save is increased by 1d10.