Apart from your usual rewards (Food, Gold, Gems, Monster Cells, and Rank-Up Resources), there’s a chance you might find two really special objects: Silver Stones and Gold Stones.

By collecting certain amounts of Stones, you’ll be able to
open a Silver Chest and a Gold Chest. However, you’ll need to get all the required Stones to open each of the chests!

Once unlocked, the rewards inside the Chests will go to your Treasure Box with all your other claimed rewards, and the Chests will reset until the next time you collect enough Stones.

When you exit the Treasure Cave, you’ll leave all your unused Stones behind! The next time you enter the Cave, you’ll start collecting them from zero.