Very simply, just have you against three cpus. I'm not entirely sure I see why implementing it would be a problem.
And if it would, it doesn't need to be part of the main game. BW didn't featire triple/rotations particularly often, and many people forget this but before Emerald completely overhauled the trainers, Ruby/Sapphire had an atrociously low amount of double battles.
Wait, I'm not sober enough. I may still need to reread how the Battle Royale works, sorry....
I won't expect that in the story though, I wrote too much. But in the post-game is what I'm interested.
Which is why I said little. Still made me a little happy.Seals Bark. I'm sure Disarming Voice is more of a flavor thing than anything. I won't say that it having a final evolution be Water/Fairy would be neat, but it's definitely too early to say.
Well, Fennekin can learn Grow Punch too somehow as in past XY footage (ah, nostalgia of her type conundrum and Fire/Fighting fear). But then she can also learn Psybeam naturally.