World B is the world of Dissidia Final Fantasy and its prequel Dissidia 012 Final Fantasy, though it is only named and shown in the prequel. It is a near-mirror image of the world of the original Final Fantasy, which is called World A in Dissidia 012. In Dissidia Final Fantasy, it was implied the world was formed from fragments of other Final Fantasy worlds that had been destroyed. Dissidia 012 Final Fantasy retconned this with World B, and the usage of gateways to explain how the characters can appear in parts of other worlds.