Wait... So I need a Garchomp that can only learn level-up moves and Surf, but he is not allowed to learn Outrage/EQ/whatever? And then I have to solo the Ice-type gym, and make it kick Cynthia's Garchomps ass.
Now I wonder how I'm gonna get a legit Garchomp before the 7th gym, but sure. Any rules on leveling it?