THE ENTIRE LEAGUE IS OUR RIVAL!!! 

But really, I feel like QCC could have a few bids for Rivals. Last season the Raptors knocked us out of the playoffs. While it maybe a rather short time (as far as I'm aware) this is usually how rivalries start. See the Oilers and the Hurricanes as an example. Though I wouldn't say there is a lot of bad blood there. At least not yet. It's more a soft rivalry with COL having some bragging rights over QCC. At least for now.

Carolina could be another group that you look at. 7 and Flex are pretty good friends, I think. They really could hate each other but they act like their friends. There is a rule that if 7 shows up in the QCC locker room, we point (fake) guns at him. If that's not rivalry status I don't know what is. With the two GM's being friends though. This is more of a friendly rivalry and not a blood bath. 

NBB is probably my selection for QCC's most "hated" rival. We love beating them. We love watching them lose. Any time they're below us in the standings, it's cause of celebration in Quebec.