The other day I saw (watching random battles) this Butterfree that really surprised me, the set can be incredibly broken if you don't pack some specific counters.
Butterfree @ Leftovers
Timid 252 spe / 252 spa /4 something (I guess)
Just bring it in against something slower, sleep it, quiver dance, whirlwind, repeat, since the sleep counter resets on the forced switch, there's nothing the oponnent can do to stop it from reaching +6. There's a good amount of things that can counter it, but it's pretty legit set against a shit ton of things.
Taste the Rainbow Motherfucker!
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