Artijar’s Beyond Insanity

You choose one creature in range that has less than 4 current hit points times your level(max 40). The target gains 1d4 levels of insanity for the duration and must make a DC 13 wisdom saving throw or become charmed. A creature charmed in this way will do whatever you want it to do including intentionally harming itself or others it cares about. All damage taken by the target while charmed damage does not do anything and the target remains at its current hit points. Once the spell ends all damage taken by the target all comes back at once as necrotic damage.