Found in Irithyll of the Boreal Valley.
Upon reaching the swamp area below the city, past the dark room filled with Irithyllian Slaves, follow the right side to find the corpse of a Man-grub holding the spell. It is guarded by two Sewer Centipedes.
Restores HP for the caster and nearby allies equal to 5.5 times the Spell Buff of the catalyst. This multiplier is reduced when using a catalyst that also scales with Intelligence, such as Crystal Chime and Sunless Talisman.