I don't know how to actually
beat Cross. But in my book, when you kill the final boss, watch the credits, and then see the 'Fin' screen, that is beating a game. But if
beating the game means killing every insane boss, getting everyone's ultimate weapon, and seeing every single ending... GOOD GOD NO. I can barely do that in FF7! (damn you, Emmy and Ruby WEAPON...)
Hmm... Crono, Lucca, and Robo... never thought of something like that. Last try ended with Magus, Marle, and Frog, and the try before that ended Crono, Marle, Magus. I discovered Double Cure, so...