In-Game unlockable Soundtrack Tip: To unlock the song “Reach for the Stars”, you must collect all five red rings in Planet Wisp Act 2.
Avatar Award Tip: SPOILER! To unlock the three avatar awards (Eggman’s bottoms, Eggman’s Top and an Eggman Avatar head) you must defeat all rivals and bosses (including the final boss) on hard mode.
Xbox 360 Achievement Tip: There’s a secret achievement called “Color Power”, which you get for finding an exceptionally well-hidden red ring in Planet Wisp Act 2. The red ring is located on a mine cart section, where a bunch of golden rings will alert you there is a rocket wisp section above. Before you get here, snag the Wisp capsule that seems useless but is on your path anyway, then just sit on the mine cart until you come across the rocket wisp section. Aim dead center, and you should crash right into the red ring. Clear the level after you’ve done this, and the achievement is yours!