The Stealth Achievements are three Achievements a player can accomplish in Audiosurf. They are gained by getting the Stealth bonus using Ninja Mono on a song of a certain length. There are three Stealth Achievements:
Stealth Adept: Using Ninja Mono, earn Stealth. 3 minute minimum.
Stealth Master: Using Ninja Mono, earn Stealth. 7 minute minimum.
Stealth Legend: Using Ninja Mono, earn Stealth. 11 minute minimum.
Note: These achievements must be earned one at a time. For instance, if a player attains Stealth Legend without earning Stealth Adept, the latter achievement will not be earned as well. Three rides are the minimum required to gain all three achievements.