Pile of Sacrifices are unique secrets found in Castlevania: Lords of Shadow 2. They look like large decorated vases with a tiny statue of a demonic being holding a large knife on top. They act like Pain Boxes.
When Dracula uses the knife to drop some blood inside the vase, he gets a bonus: either a Nail of Kleidos, or the possibility of holding one more item per relic (up to 5 relics of each sort). The bonuses found in the Piles of Sacrifices are random.