Pokémon is a real money-maker for all concerned right now, but the franchise has a strong commercial history behind it, and that has led to some interesting spin-off titles - Pokémon Conquest being one notable example.
However, had that particular release not happened we could well have been playing another game which mixed Pocket Monsters with the world of Fire Emblem.
According to Nintendo's Hitoshi Yamagami and Kaori Ando - who have been speaking to Nintendo Dream - this very idea was raised a while back, and when it never went anywhere, Tokyo Mirage Sessions #FE was born:
ND: Please tell us what led up to the planning of Tokyo Mirage Sessions #FE.
Yamagami (Nintendo Producer): 5 years ago, Ms. Ando proposed a plan [for a crossover], saying "You know, I think FE and Pokemon's rules are pretty compatible!" Though I agreed with her, by chance the Pokemon group had already proposed what eventually became Pokemon Conquest at the same time [so we were unable to follow through].
Ando (Nintendo Director): Yes, which I was in charge of too.
Yamagami (Nintendo Producer): As the plan was a secret, she was put in charge of that first. (Laughs). And then, it took her less than a week to say, "Here's the next plan." The new plan was a collaboration with Atlus. At that time, new games like Xenoblade and Pandora's Tower were coming out, and, because I myself was quite interested in Atlus's games, I figured "This could work!" At first, we made informal plans within our own small group, but…
Takata (Atlus Producer): At that time, the organization itself was undergoing changes. and it was almost impossible to deal with Atlus as a second party, and so we almost decided to give up on it. After roughly 2 years, we heard from Hiraoka (board member at Atlus), "Let's try to collaborate and level up by making an RPG together." After that, we attempted to contact Nintendo repeatedly, asking "Do you want to bring that RPG to life [with us]?"
Yamagami (Nintendo Producer): We replied immediately with, "Let's do it!" We then quickly began to draft plans for the game, still only having a rough idea of what it would be. And so, we released an image that showed, "Shin Megami Tensei Meets Fire Emblem" to the public.
Would you have liked to have seen this game come to pass? As ever, let us know by posting a comment.