You've completed the main event with time to spare; now test your skills in Rainbow Falls, the limited time bonus challenge! Missions will unlock after early completion of an event for expert players to collect extra prizes!
Each challenge is comprised of a series of missions that must be completed in sequence to win. If you fail any mission, you will have to start again from the first mission in that challenge. For example, if you fail to complete the third mission in the second challenge, you will lose your progress and begin again from the first mission in the second challenge.
If you are experiencing issues with Rainbow Falls resetting after successfully clearing a stage, please attempt this fix: fail one time at your current Rainbow Falls level before attempting again, it should allow you to move on the next time you play successfully.