[PkmnMstr]

I wouldn't limit it to particular Pokémon. Been playing around with this crossover idea for a while.

Marvel Disk Wars for example. If you've never seen it, heroes and villains get trapped in Disks, and they go around collecting them all. But you're able to "capture" villains once they're defeated.

With that same concept, the "Core Medals" should be empty. Would serve the same purpose as Poké Balls. You would still battle and capture wild Pokémon the same way you always have.

Trainer battles is where it would differ. The Driver would not be a unique piece used by a single person. It would be standard issue to trainers. So when you battle other trainers, you load up whatever three Pokémon you like, and transform. This directly connects you to your Pokémon. The stronger your bond, the more powerful your cores are. The cores would not be designated head, arms, or legs like the OOO cores. You can use any Pokémon in any position. This increases the number of combinations and strategy.

I'm aware that this is more an OOO version of Pokémon than a Pokémon version of OOO, but it blends the elements a lot more cleanly. If you have set combos and cores, any number of people would say "but this Pokémon would be better for this combo because reasons"

The more direct way of doing a Pokémon version of OOO would be to simply use Pokémon equivalents of the animals used in core medals, but that's not as fun.