Bethesda is reportedly suing Warner Bros. over the Westworld mobile game, which it claims uses Fallout Shelter code.
According to TMZ, Bethesda is suing Warner Bros. and Behaviour Interactive, the developer of the game. In court documents, Bethesda reveal it contracted Behaviour in 2014 to work on Fallout Shelter before Behaviour went on to make the Westworld game for Warner.
Fallout Shelter is a building and people management sim with a cute art design where you play the vault overseer. You have to keep your vault dwellers alive, playing Cupid to get them to have babies, while all sorts of things go wrong in the vault and, when you can, send your people out into the wasteland to gather resources. It looks like this: