Bethesda Softworks is filing legal action against Warner Bros. and Behaviour Interactive, the co-developers of Fallout Shelter, stating that the recent Westworld game was a rip off of Fallout Shelter.

In the lawsuit, Bethesda alleges that Westworld, “has the same or highly similar game design, art style, animations, features and other gameplay elements” as their own title, according to Polygon.

Bethesda also claims that Behaviour had also used their copyrighted code, claiming, “To bring the Westworld mobile game to market, Behaviour and Warner Bros. utilized Bethesda’s intellectual property without authorization to develop a mobile game with the same or substantially similar gameplay experience as that provided by the copyrighted Fallout Shelter mobile game.”

The allegations also state that the developer also used the same concept of 2D sprites in a 3D environment while creating underground rooms, which are present in both games.

You can read the full document for the lawsuit here.