Try a special sweep.
Timid.
Leaf Storm, Focus Blast, Giga Drain, (not sure about fourth, but something to give it good coverage).
Choice Specs/Life Orb.
There's also a Sub/Stall build you could go for, which is pretty fun.
Timid
Toxic/Leech Seed/Focus Blast, Substitute, Giga Drain
Leftovers
He doesn't have much bulk though, so others can do it better.