BUTTERFREE
Stats: 60/45/50/80/80/70
There are two reasons for this. The first is that the Dream World granted Butterfree Tinted Lens, giving it an almost unresisted Bug Buzz. THe second was Quiver Dance. If you have been battling at all over the last year or so, you know exactly what Quiver Dance can do for a Pokemon. With the second-best boosting move in the game under it's wings, people looked at Butterfree in a new light. Still having Sleep Powder, Roost, and Substitute with it, Butterfree gained the ability to wreck unprepared teams.
Butterfree @ Leftovers
Ability: Tinted Lens
EVs: 252 SpA / 4 SpD / 252 Spe, Timid Nature
Moves:
Sleep Powder
Bug Buzz
Quiver Dance
Roost/Substitute/Giga Drain
This set is simple: Either come in on something that you force to switch out, such as Sawk's Choiced Close Combat, and set up a Quiver Dance, or put something to sleep. THanks to TInted Lens, Butterfree's Bug Buzz is nearly undesisted. The least slot can be used for free setup, or healing. Overall, the original butterfly can pose a huge threat to teams.
So what do you think of Butterfree? Let me know by replying, and thanks for reading!