How to refill event energy?

The purchased event energy is added to your inventory as an item. In order to use it, you need to:
  1. Open the event screen.
  2. Tap on the energy bar on the top of the event screen.
  3. You will see Energy Refill window.
  4. Tap "use pack" to add energy.
Unused event energy items will be saved for the next event with the same type.