A Tomb is a lootable location only found in Desert worlds. They always hold 1-2 Mummies, but can also yield Moon Stones in Expedition 3 - 6. In order to loot a tomb, the player must choose to open the sarcophagus and risk having to fight a Mummy enemy before being able to loot.
The chance of discovering an enemy mummy decreases with higher Sanity.
Tombs are one of the few locations who's presence is indicated on the World Map when choosing a destination. Some deserts have no tombs, but others have as many as 3.