My friends and I have finally made it through mission 10 and are going to start the bonus challenges next week. I am so happy with this game! I really liked the certificate and letter in the reward envelope.
I have only but a single gripe - there were no in-game rewards! I was almost expecting there to be 4 codes for summoner icons or a ward skin or something small, but, nope... oh well, still a great game! I will just keep sporting the MvM icon I bought!