The strongest that's actually in the BW2 Pokedex is Black Kyurem and White Kyurem, who have stat totals of 700.
Of course, you can get all the Pokemon by trading etc, and Arceus is still the strongest of all time at 720.
700 BST. That insane Attack. Reasonable defenses and Speed, and good Special Attack.
How to change your username
How to add a user avatar
Why was my post hidden?
Flags vs Downvotes
Official PokemonDb League
Type a Pokemon name, type, move or ability to see instant results.