A composite Kaiba is ridiculously strong, in my honest opinion. Obelisk speaks for himself, Critias is basically making up cards as he sees fit for the situation, BEWD/BEUD is still a good beatstick (especially in the anime), and Shining Dragon is broken in the movie as it was made to beat the God Cards (how it would beat Ra, I don't know). Plus, all of his other broken cards like Ring of Destruction, Soul Exchange, Enemy Controller, Chaos Emperor Dragon, the list goes on. Kaiba was the man for broken cards in Duel Monsters, excluding the obvious choice of Dartz. Going by anime standards, there's no way Kaiba could lose this. In real life he'd probably get dead draws up the ass with all those powerful monsters, but yeah.