Nature: Modest (won't be using atk. anyway)
EVs: 252 sp.atk 252 hp
he would make a good tank sweeper
Leech Seed - heals every turn and weakens the foe at the same time
Sunnny Day - it may up fire moves, but getting one-move solor beam is worth it.
Solarbeam - 100% acc., strong, and one turn with sunny day
Synthesis - if sunny day is on, this will resore 2/3 hp. if your hp is low, use this, plus your left overs, plus your leech seed, you get almost all your hp back in one move.