The location is intended to be the most challenging and tense in the game. It is unlocked after finishing any of:
Tharis Island hosts a number of abandoned faction bases, lush ravines, alien Progenitor artefacts and a labyrinthian cave system.
Tharis Island was originally discovered by Korolev years before The Cycle (storm) hit. Large parts of the cave system has not been reached before by any Faction or human. Those who went too deep either lost their lives in the caves, or came back mad. Thirty years after the discovery of Tharis Island, prospectors are invited to explore the island and uncover its secrets.