The Arks of the Cosmos are five long-lost gravity-manipulation devices, designed by the ancient Babylonian civilization - ancestors of the Babylon Rogues. Large, metallic, ring-shaped objects, the Arks glow brilliant blue when activated, and are worn round the wrist like a bracelet by various characters during Sonic Riders: Zero Gravity, the only game in which they appear. In a sense these devices are the true antagonists of Zero Gravity, as they co-opt Eggman's robots and almost destroy the world via the "Lightless Black".
Much of the Arks' true nature is only (speculatively) revealed at the very end of the game, when Tails muses back on the meaning of their recent adventure. The Arks were part of a black-hole-powered drive system for Astral Babylon, an interstellar vessel which brought the Babylonians to Sonic's world in ancient times. Some sort of malfunction required the spaceship to jettison the Arks in orbit and crash-land on the planet; stranded, the Babylonians converted their ship into an aerial city, Babylon Garden. Eventually losing their high technology, the Babylonians' extraterrestrial origin faded from memory, by Sonic's time existing only as faded ruins and myths amongst their distant descendants (like the Babylon Rogues).
Thus things might have continued, if not for Doctor Ivo "Eggman" Robotnik. Some time before the events of Zero Gravity, the fat scientist discovered one of the jettisoned Arks within an impact crater in the desert near Monopole. As well as being able to manipulate gravity, the Arks seem able to function as high-power computers, and Eggman extracted a piece of the Ark for use in his Meteor Tech Mother Computer atop Crimson Tower.
By coincidence or design, other Arks began to be discovered after the Mother Computer was activated. Jet the Hawk extracted one from the old Babylonian ruins of Gigan Device, while Tails, SCR-HD, and Megalo City's museum picked up Arks that fell as meteorites. At this point, the Mother Computer went berserk, with Babylonian programming taking control of the networked SCR-GP and SCR-HD robots, guiding them to collect the 5 Arks together and bring them back to Babylon Garden. The majority of Zero Gravity sees Team Sonic and the Babylon Rogues avoiding the robot's pursuit, and trying to figure out exactly why they want the Arks.
At the end of the Babylon Story, SCR-HD steals the five Arks from Wave at the top of Crimson Tower. Returning them to Babylon Garden, however, prompts precisely the disaster which the ancient Babylonians were trying to prevent thousands of years ago: the black-hole drive overloads completely, obliterating the Garden and threatening to devour the planet itself. Sonic flies his Extreme Gear into the maelstrom to battle Master Core: ABIS - SCR-HD transformed under the influence of the Arks - and manages to stop both the robot and the singularity. The fate of the Arks after this final battle is unknown; they may have been destroyed by the black hole, scattered, or simply resting peacefully on Astral Babylon, now back in orbit.
|Sonic Riders: Zero Gravity|
| Hero Courses:
|Items in the Sonic the Hedgehog Game Series|
|Collectibles||Ring | Red Star Ring | Emblem | Chaos Drives | Material|
|Power-ups||Shield (Water, Lightning, Fire, Gold) | Invincibility | Power Sneakers | Power Core | Light Cores|
|Level Objects||Monitor | Spring | Spikes | Checkpoint | Time Warp Plate | Signpost | Goal Ring | Giant Ring | Capsule | Button | Bumper | Speed Booster | Chao Container|
|Powerful Items||Chaos Emeralds | Super Emeralds | Master Emerald | Time Stones | Chaos Rings | Precioustone | Sol Emeralds | Jeweled Scepter | World Rings | Excalibur | Phantom Ruby|
|Weapons||Piko Piko Hammer | Chaos Energy Cannon | Caliburn | Wispon|
|Devices||Remote Robot | Combi Confiner | Mother Computer | Nega's Camera | Arks of the Cosmos | Miles Electric|
|Other||Chili Dog | Scepter of Darkness | Cacophonic Conch|