Horizon Dawn Zero is one of Sony’s latest best-selling games; selling over 2.6 million copies just a few weeks after initial release. The success of the game marks the “biggest Debut” for Guerrilla games and confirms their place in the gaming industry.

Guerrilla has created a game that is nothing short of exceptional, and the reaction we have seen from fans–from hours and hours of gameplay streaming to endless photo sharing–shows just how impactful it has been. Say Shawn Layden, the Sony Interactive Worldwide Studio chairman in a statement.

Also, Guerrilla’s managing director, Hermen Hulst confirmed that they are working on an expansion for Horizon: Dawn Zero but no specifics were disclosed.

Horizon Dawn Zero is an open-world survival RPG which revolves around a hunter named Aloy. The game is available for the PlayStation 4 an exclusive.