Collect all red special rings in the six main zones to unlock the abaility to toggle an unlimited boost gauge at the options menu. Note: This cannot be done in Time Attack or Versus modes.Nega-Mother Wisp final stage
Successfully complete Terminal Velocity with all emeralds. After the credits have completed, return to the game. After a quick cutscene, the final stage with Nega-Mother Wisp will be available at the very top of the world map.