The Arks of the Cosmos (星の聖櫃 Hoshi no Seihitsu?, lit. "Ark of the Stars") are five ancient, ring-shaped metallic stones created by the Babylonians that allows the user to manipulate gravity. They are a major plot device in Sonic Riders: Zero Gravity where Team Sonic, Dr. Eggman and the Babylon Rogues are hunting for them.