Death ball

You throw a ball of black shadow and hurts the it creature hits   

The first time the target would drop to 0 hit points as a result of taking damage, the target instead drops to 1 hit point, and the spell ends.

If the spell is still in effect when the target is subjected to an effect that would kill it instantaneously without dealing damage, that effect is instead negated against the target, and the spell ends.

only for cleric-death domain who have the death elemental as there patron