One of the hardest feats to pull off is switching a video game franchise from one genre to another, either as a companion title or a whole new direction.
Halo did rather well as a real-time strategy in Halo Wars after beginning as a killer first-person shooter. WarCraft took a wildly successful real-time strategy and turned it into the biggest massively multiplayer online role-playing game ever. For the Persona franchise, the leap was role-playing game to fighter, in Persona 4 Arena, released in 2012. Following that success, 2014 brought a refined sequel, Persona 4 Arena Ultimax.
