'League of Legends' quarterfinals preview: Cloud9 faces Envy and more

And then there were six. The League of Legends playoffs begin this weekend in both North America and Europe. Which teams will get through their first hurdle and get to square off against one of the top two from their regions in the semis? Here are our best guesses. 
North America
Cloud9 versus Team Envy
After some stumbles in the middle of the split, Cloud9 have returned to their dominating form. They won convincingly over Team Liquid and Echo Fox at the end of the season, and seem to be ba