since everyone is suggesting different celebi sets...
Celebi @ Leftovers
Trait: Natural Cure
EVs: 252 HP / 220 SDef / 36 Spe
Calm Nature (+SDef, -Atk)
- Perish Song
- U-turn
- Recover
- Giga Drain
as people mentioned before perish song to help against cm reunicles and u-turn so youre...