Sonic Riders: Zero Gravity
Sonic Riders: Zero Gravity is a hoverboard racing game developed by Sonic Team and published by Sega for the PlayStation 2 and Wii. It is the fifth racing game in the Sonic the Hedgehog series and the second part of the Sonic Riders trilogy. A port for the Xbox 360 was canceled during development, while a sequel, Sonic Free Riders, was released exclusively for that system in 2010. Zero Gravity's gameplay is largely similar to that of its predecessor. The characters ride different types of hovercrafts called "Extreme Gear". In addition to the mechanics from the previous game, Zero Gravity adds a new gameplay system based on gravity, replacing the "fuel" system of the predecessor. During the race, a character's gravity points (GP) increase as they perform tricks and other actions. If players accumulate enough GP when they reach certain areas of the track, they enter a zero-gravity zone where they can perform one of two maneuvers. A Gravity Dive creates a small black hole that directs gravity forward onto the track, giving the player a powerful boost in freefall that is enhanced by hitting nearby objects that the hole displaces, such as cars or signs. Alternatively, Gravity Control can alter the gravity of the track, allowing players to reach otherwise inaccessible areas and shortcuts. Gravity Drift also allows players to maneuver around sharp turns more easily.
Story
The Babylon Rogues pick up an Ark of the Cosmos, one of five relics that can control gravity, and plan to use them all to power Babylon Garden's warp drive. More arks fall from the sky, and one of them hits the Crimson Tower of the technology company MeteoTech. As a result, the robots inside go crazy and start a worldwide rampage. Sonic, who is traveling with Tails and Knuckles, finds one of the arks. He is attacked by the robots, but uses the power of the ark to escape. During the chase, the trio meets Amy, who has also found one of the arks. The four make their way to MeteoTech, where they encounter the villains and Storm pursues Amy to steal her ark. The others venture further in, where they discover the owner of the company, Doctor Eggman. Eggman reveals that one of the robots, SCR-HD, was hit by the Ark, which hit Crimson Tower, making it sentient and giving it leadership over the other robots. The robots are now trying to get all five arks, one of which Eggman used to power the mother computer that controls all of MeteoTech. Amy hands over her Ark of the Cosmos to Storm, but the two are attacked by a robot. Suddenly, the Ark explodes and Storm finds another Ark inside and runs to find Jet. Eggman steals the villains' arks and retreats to Crimson Tower, using them to control all the robots in the world while the villains chase him. Sonic and the others retrieve Amy and travel to Crimson Tower to shut down the mother computer. There they meet the villains and Jet challenges Sonic to a final race where the winner gets all the arks. The two storm the tower, take back the arks and take out all the robots. The resonance of the arks summons the Babylon Garden and Sonic hands over his arks to Jet. Before they can leave, SCR-HD appears, steals the Arks of Cosmos and retreats to the Babylon Garden. SCR-HD activates the Arks and reveals an ancient spaceship inside Babylon Garden that creates a giant black hole capable of destroying the planet and transforms into a monstrous robot called Master Core ABIS. Eggman escapes while the heroes and villains make their way to the ship and defeat ABIS with Gravity Dives, shutting down the Arks and stopping the black hole. In the episode, Tails speculates that the Babylonians' ancestors were aliens who lost control of their ship and sent the Arks into orbit to shut it down before crash landing, hoping that the Arks would one day return to the surface so they could return to their home planet. Jet arrives and challenges Sonic, who happily accepts.