I'm mostly new to competitive pokemon and X & Y is really pushing me away from it for one reason. Fucking Mega-Blaziken. I've lost 7 online battles in a row. Most of the time I'll destroy their first two pokemon, at which point they'll throw out Mega Blaziken and wreck my entire party.

So can anyone who has some experience tell me what the fuck I'm supposed to do in this situation? It's infuriating, I've tried several pokemon but I can't seem to find any decent counter to this cheap asshole.