The last battle of set 8 in the last colleseum. That guy is an UbEr AbuSeR, his kyogre's choice scarf is a serious irritation in its own right, I mean come on what can outrun that! And his pokemons stats I swear are way to high. my guys can barely dent them.
And the final rant is just the fact he uses ubers. They should have thier own colleseum. I feel bad if I beat the 3 trainers before him with ubers.