The game was officially announced on January 23, 2013 as part of a Nintendo Direct presentation. The trailer showed artwork of several characters from both series, and revealed the game was going to be developed by both Atlus and Intelligent Systems, the first joint project between the two development teams. The trailer concludes with the message "Development in Progress". While initially speculated by journalists that the game could be any genre due to the trailer's vague nature, Atlus confirmed the next day that the game will be a role-playing game.
At E3 2014 in June 2014, Nintendo producer Hitoshi Yamagami said that despite the lack of updates since its announcement, the game is still being developed, and that things are going according to schedule, but that he could not reveal any more details at the time.