Toxic Deluge

You sadistically cut yourself, pouring out a bit of your lifeblood. Doing so, you sacrifice a number of hit points that does not reduce your total to 0 or lower, forcing every hostile creature you can see within range to make a Constitution saving throw. On a failed save, they take necrotic damage equal to the amount of hit points you sacrificed, and become poisoned for the duration. On a successful one, the spell has no effect, your wound magically heals, and you regain the amount of hit points you sacrificed at the beginning of your next turn.