Balloon Bonanza is the third Challenge Act of Sky Sanctuary Act 2 in the console/PC version of Sonic Generations. It is unlocked after clearing every Stage in the classic era and is playable only as Modern Sonic.
In this Challenge Act, Sonic must use Balloons of various colors scattered throughout Sky Sanctuary Act 2 to reach the Goal Ring as quickly as possible. Boosting isn't as effective in this Challenge Act as it normally is, but the Homing Attack comes in handy to reach Balloons a second faster and cut down on the overall time it takes to reach the Goal Ring. The Stomp also helps near the end, when Sonic must land on a platform in the air that is surrounded by Balloons and a couple of EggRobos. Once Sonic reaches the Goal Ring, the Challenge Act is completed, and the player is ranked according to his/her time.