User blog comment:TinyCastleGuy/Let's Play/@comment-4652747-20111231123533/@comment-1455034-20120103140743

649 + the 200 versions of MissingNo.. Some Pkmn also have form differences, although it does get a little hectic (Spidna, a Pkmn introduced in Gen. 3, as 1,000,000 forms, what form you get found out by a mathematical formula).