How do you charge the Grail?

There are two ways of charging the Grail:

1. Attack another clan. If you win, you get some of the energy from your opponent clan’s Grail. If you lose, your Grail’s energy remains the same. To issue a challenge to another clan, tap Select Opponent on the Grail home screen. 
2. Sacrifice objects. All players can convert game objects into Grail energy. You can convert items, scrolls, boosters and books.
   Read more: How do you sacrifice game objects to charge the Grail?

Note! The level 1 Grail is charged automatically within 72 hours. This only happens once. Once the level 1 Grail is at 100% charge for the first time, players can charge the Grail only in the two ways described above.