Expunge Blood

Make a ranged spell attack. On a hit, the target
takes 6d8 necrotic damage and it's HP maximum
is reduced for the same amount, as your touch
absorbs its body's life force.
Undead, Constructs, and Elementals are immune
to this spell.
At Higher Levels. When you cast this spell using
a spell slot of 4th level or higher, the damage
increases by 2d8 for each slot level above 3rd.