Reah of Thorolund gives this miracle to the player in exchange for freeing her followers, Vince and Nico, from their torment as hollows. These three are encountered early on in the Tomb of the Giants.
As its name suggests, the Replenishment miracle steadily replenishes lost HP. The user recovers 10 HP/second for a minute, or 600 HP in total.
Replenishment benefits from miracle synergy. It replenishes 20% more health with the synergy boost, and 40% more health with double synergy.