Barrel Ring Bonus is the first Challenge Act of Rooftop Run Act 2 in the console/PC version of Sonic Generations. It is unlocked after clearing every Stage in the Modern era and is playable only as Modern Sonic.
This Act takes place within a slightly modified version of Rooftop Run Act 2. The stage's layout has been changed by stone pillars and Spike Traps, and additional platforms have been placed at various locations.
The Act is similar to the normal version of Rooftop Run. The player begins where the Eggman Flying Battery would normally drop Spiked Barrels on Sonic, and must collect the required amount of Rings from Golden Barrels on their way to the Goal Ring.