Shadow of the Tomb Raider

In order to decipher a Monolith, which are found in various regions of the game, you will first need to know an appropriate dialect at a given level. You can increase dialect knowledge by uncovering relics and interacting with murals. After deciphering a Monolith, you are then given a hint that will lead to nearby treasure.

For more information, please refer to the "Completionist" achievement below.