Sacrificial Siphon

You touch another creature and lay a curse that drains the target’s vitality and transfers it to you. The target must make a Charisma saving throw. On a failed save, the target is cursed for the duration. While cursed, the target must subtract 1d4 from its attack rolls and ability checks, and when the target takes damage, you can take a Reaction to gain 10 Temporary Hit Points. On a successful save, you gain 5 Temporary Hit Points, and the target must subtract 1d4 from its ability checks until the start of your next turn.