How do you sacrifice game objects to charge the Grail?

There are special slots at the bottom of the Grail home screen that players can put items in. Wardrobe items (skins, masks, items, auras), scrolls, books, boosters and other game objects can all be converted into Grail energy. Converting takes time, but you can speed it up for coins.

Each player has their own slots, and all clan members can help charge the Grail. You can open up new slots for coins.