Ravenous Skull
Ravenous Skull
Wondrous item, very rare (requires attunement)
This tiger skull is charred black from hellfire. While you hold the skull, as a bonus action on each of your turns you can expend a single spell slot and convert its magic into healing energy. You regain 1d8 hit points, plus an additional 1d8 per level of the spell slot expended. If you would regain hit points past your hit point maximum, you gain excess as temporary hit points that last until you finish a short rest.
Ref: TPKB1 p219