Smeargle @ Focus sash/
Nature jolly- 252 speed evs, 252 hp evs/
Transform (I heard that transform copies the foes stats and stats changes except for hp and my Smeargle will still keep his speed evs)
Substitute(After using spore i was thinking i could set up a substitute before i transform and if they stay sleep long enough i can set up leech seed too)
It is still a nice idea, but perhaps have another move to help things out. Maybe a recovery move for added health, you could fine tune the set a bit to give it baton pass and you can send that health restoration to another pokemon on your team.