So I was looking at Poliwrath sets on Smogon, and i thought I'd come up with my own, for a double battle. I'm new to movesets, so don't blame me if it sucks.

Poliwrath @ Leftovers/Life Orb
Adamant / Water Absorb
252 Att / 116 HP / 140 Spe
~ Substitute
~ Focus Punch
~ Belly Drum
~ Waterfall

And a second pokemon with surf. Doesn't matter who. Make sure your Poliwrath is faster.

When you send them out, Use Belly Drum on Poliwrath, and the other pokemon surf so he heals your Poliwrath up, while getting some damage on the foe. Then do whatever with the other pokemon. If there is any pokemon that can learn Surf AND Follow me it would be perfect, because then you make make the opponents focus on that pokemon, while you set up a substitute, and then go for a focus punch. Waterfall is just for a Physical STAB move.

Possible second pokemon:

Smeargle @ Focus Sash
Bold / Technician
252 Def / 252 HP / 4 Spe
~ Follow Me
~ Surf
~ Helping Hand
~ Stealth Rock

Furret is the only poke with surf/follow me so you'd be better with smeargle.

Poliwarth should have a salac berry, and you should wait to surfheal him on the 2nd turn so poli can make a sub to activate the berry.

Then you just need a strong move that can wipe both opponents with, or you'll just be killed by the other. Rock slide is the only available option, which will be too weak to sweep early with, and maybe even too weak for late game.

Also there's the problem of what your opponent is doing during these 2 turns...