Ghost is a Gear Part that appears in Sonic Riders: Zero Gravity. It is an Extreme Gear component that can turn both the Extreme Gear and its rider invisible and removes them from the course map.
Ghost is an installable performance-enhancing component for Extreme Gears. Its actual appearance is unknown, though it is presented as an icon on the head-up display in the top-left corner of the game screen. Its icon is a light green-colored circle with a black stereotypical ghost sticking its tongue out, inscribed in it.
In the game, Ghost is permanently installed into only certain Extreme Gears. When used, Ghost makes the playable character and his/hers Extreme Gear completely invisible to the opponents participating in the race. For the player using Ghost, however, his/her playable character only becomes transparent, allowing the player to still perceive his/her character. Additionally, Ghost also makes the user's character icon disappear from the course map when activated, making it impossible for both the player and opponents to determine the user's location on it.
In gameplay, Ghost and its ability will be disabled when starting a new race. To activate Ghost, the player must press one of the following buttons after collecting a certain number of Rings:
Wii (remote) - sideways
Wii (remote) - forward
Wii (Nintendo GameCube Controller)
When activating Ghost, the player's Rings will be reduced accordingly by the number needed to enable it and the Extreme Gear is surrounded by an orange void, indicating that the Gear Part coming into effect. The following Extreme Gears come equipped with the Ghost: