I realize I'm the best and the only reason your team did so well is because of me.
Regardless, I'll post some stuff.
The only real, actual, serious problem this team encounters on a regular basis is Banded Terrakion. That thing's a bitch. There's only one Fighting resist on this team, and it's 2HKO'd by Banded CC and OHKO'd by Banded SE/X-Scissor. Hippowdon, despite its massive physical bulk, is 2HKO'd with good damage rolls after a layer of Spikes and Stealth Rocks. That's scary stuff. I didn't really know what to do about this weakness so I just tried to play around it. It's doable, but difficult. I ended up using Pursuit with Stoutland on a 7% Terrakion once.
Anyways a couple changes:
- I used more Speed EVs on Shaymin to beat Adamant Lucario and Timid Heatran. I don't know if this version has that or not, I couldn't be bothered to check.
- On DAT BIG DOGGY STOUT, I used Return, Wild Charge, Fire Fang, and Pursuit. I never really found myself needing Ice Fang except in ONE situation where I missed the OHKO on Landorus by 1%. Pursuit is super useful in case Specs Latios uses Surf on the BandTar switch in and manages to 2HKO.
- I couldn't ever really decide between Sleep Talk and Thunder on Magnezone. On one hand, Sleep Talk is a godsend against SubPunch Breloom, who otherwise gives this team a lot of trouble. On the other hand, Thunder makes it very easy to sweep Rain teams late game, as it's usually something like Politoed, Tornadus, and X other Pokemon remaining. I ended up going with Thunder, which was the exact wrong choice, as I ended up losing one of my WCoP matches because of the lack of Sleep Talk.
- On Hippowdon, what are you doing??? Ice Fang? Please. Roar? Hello. Whirlwind, my friend, is the way to go. That way those damn Soundproof Mr. Mimes can't set up on you.
Final Comments: Great team, I've used it in maybe 500 battles and gotten great ranks on both servers with it. What a fantastic combination of Pokemon. Thanks for the shout-out to your boy NPC, I ball hard.