High-Rise Balloon Climb is the second Challenge Act of Rooftop Run Act 1 in the console/PC version of Sonic Generations. It is unlocked after clearing every Stage in the modern era and is playable only as Classic Sonic.
In this Challenge Act, the player uses the various Big Balloons that are rising upward to reach the goal. While the Challenge Act focuses more on using these balloons to rise and Cannons, some minor platforming is still involved in the act.
The player begins on a lower platform outside the clock tower. They must run inside, destroying enemies until they make it to the first balloon dispenser. From there, they must jump on the balloon and ride it up the next section. After continuing onward, the player will come across a cannon, which launches them into the stage's foreground. The player must continue upward, avoiding enemy rocket fire and jumping between balloons in order to avoid falling. The rest of the Act consists of jumping between balloons onto platforms and taking cannons to other sections of the stage while steadily climbing upward until the player reaches the Goal Plate to the left of the highest point of the clock tower.