Achieving an S Rank on a stage is the ultimate mark of mastery in Sonic Generations. S Ranks are awarded based on a combination of factors: completion time, rings collected, enemies defeated, and damage taken. The most significant factor is usually time, so speed is paramount. To get an S Rank, you'll need to know the optimal routes, maintain high speeds, avoid taking damage, and collect as many rings as possible. This often requires multiple playthroughs of a stage to memorize layouts and perfect your execution. S Ranks contribute to unlocking certain collectibles and achievements.
Modern Sonic's boost mechanic in Generations evolved directly from the tension gauge system in Sonic Rush, making trick-based energy management vital for maintaining S-Rank speeds.
While Sonic Generations prioritizes raw speed for top marks, Sonic Colors: Ultimate places a heavier scoring emphasis on the creative use of Wisp abilities.