cannibalised sustain

you touch a corpse of a humanoid or undead and the necrotic energies from you hand pour into it, causing it to shrivel up into a wrinkled, skeletal version of what it previously looked like.

you regain 2d4 + ability modifier hit points. if you reach or are at max hit points, you gain 1d4 + modifier temporary hitpoints. your healing and temporary hitpoints increases by +5

At higher levels.  your healing and temporary hitpoints increases by +5 per spell slot above 4th