False healing

Whenever you cast a healing spell, you can instead choose to deal necrotic damage to the target(s) instead. Creature(s) targeted in this manner may attempt to resist The spell by making a CON save. If the target(s) succeed they take half of the damage.

The amount of damage potential is halved if the spell does not require a roll. (For example, the spell Heal would instead deal 35 necrotic damage on a failed save, and 17 on a success instead of healing a target by 70)

In the event that a spell allows you to target multiple creatures, you must select whether or not to heal or damage, you cannot do both with the same spell.