Endless Boost is the fourth 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.
In this challenge the player has only 120 seconds to reach the goal line, the player must take excellent use of Unlimited Boost without taking a single hit. The Endless Boost skill's side effect is that Sonic can never increase his ring count above zero. So the first collison with an obstacle will kill you. Practice makes perfect is the only real strategy here. Just keep running the course, memorize each thing that killed you, and get past it the next time. You receive the Endless Boost skill as a prize for this challenge, though in some ways equipping this skill makes the game harder. This challenge is filled with Spiked balls, traps, Spike Traps, Balloons and electric fields. The time needed for a S rank is 00:50.
- ↑ Sonic Generations Official Strategy Guide pg. 202