I thought of something stupid, but I tested it out and it easily crippled a team (though I ended up losing because I was only using 2 Pokemon... http://pokemonshowdown.com/replay/gen5ou-61697449)
Anyways, without further ado, here it is!
LOLZ (Pineco) @ Leftovers
IVs: 0 HP
- Pain Split
The other 3 moves don't matter, pain split does.
Pain split assures that you stay at full hp, as long as you don't get multihitted
The rest is just there for the lolz
And yes, this is serious