I've been having some fun putting together a potential challenge team, and a wild Slaking sweep appeared! Admittedly, my opponent wasn't very good, but it does illustrate the incredible power that Slaking has when unchecked. Battle replay is here:
I'm still working out the kinks (mostly whether or not to replace Hydreigon and/or Vaporeon), but I like the core of Cofagrigus and Slaking for some major shenangians. Once I'm happy with it, I'll breed them up (plus 2 to help with doubles that are yet to be determined) to have my own fun run through of the league.
Shout out to treecko4ubers for pointing out this evil, evil strategy to me.
However, this got me thinking about team creation and coming up with a shell of about 2-3 pokemon for your team and building around them.