Ideally it should be 3 Gen 6 OU Pokemon, but I'm not sure if there's enough if you don't count Megas.
Greninja, Aegislash, and Talonflame would've been perfect, but Aegislash is ban and Greninja is guaranteed to be banned soon, so that's no longer an option.
Greninja, Aegislash, and Talonflame would've been perfect, but Aegislash is ban and Greninja is guaranteed to be banned soon, so that's no longer an option.