Hey I'm new to breeding/competitive battling, so I don't understand some things. How do tiers work? I was planning on using a Blaziken for my team in X/Y, but read somewhere that he was in the Uber tier, and I guess is banned. So, if I battle random people online, can I not use him? Or are the tiers just for going to competitions?

I was planning to baton pass a focus energy, but the only other pokemon that could learn both are Drifblim and Scizor, at least that I know of. Any other ways around this?