This is for the Mt. Battle in Colosseum Mode, I have already cleared the one in RPG mode.

I'm kinda new to making Ru/Sa teams... so let's see here. I need a 6th party member, and it has to be obtainable in Ru/Sa/Colosseum. So, let's do this. ANY and ALL suggestions are welcome (including HOLD ITEMS).

Blaziken
Sky Uppercut
Blaze Kick
Rock Slide
Bulk Up

Flygon
Earthquake
Crunch
Flamethrower
Dragon Claw

Ludicolo @ Leftovers (with RAIN DISH ability)
Surf
Ice Beam
Giga Drain
Rain Dance

Mightyena
Shadow Ball
Return
Roar
Toxic

Grumpig / Gardevoir(which one should i use?)
Psychic
Thunderbolt
Substitute / Calm Mind
Rest / Reflect

And of course... #6. Help?