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On the planet Zi, Zoids are no longer used for military combat; instead, they are now being used for sporting events known as Zoid battles. The Zoid Battle Commission oversees these battles, enforces the rules, and declares the winners. In the midst of fierce competitions, one team aspires to rise to the top: the Blitz Team! With the help of Bit Cloud and his Liger Zero, the Blitz Team will compete against not only regular foes, but also the talented Harry Champ and the criminal organization known as the Backdraft Group!
K—an agile mech pilot in Neo Seoul police's high-speed mobile unit—specializes in chasing down and eradicating terrorists. His duty has always been to protect the citizens, and he's given little thought to the mega-corporations that run the city. But when an ordinary arrest explodes into a nightmarish battle, K is painfully forced to question his convictions. Stripped of all sense of right and wrong, K must make a terrible choice—either join his enemies, or lose all sense of justice!
The series takes place in the year 2400, where the world is controlled by the "Solar System Alliance." The reason the Alliance was able to take control is because they wield mobile weapons. Those humanoid weapons use "Cyclonics" electric chips that convert the superpowers and wisdom bequeathed to mankind into interference power. These humanoid weapons which amplify their pilot's psychic powers are called "Titanic DOWLs," or just "DOWLs" (Defender Operated by Wired Linkage). DOWLs do not lose to other weapons, and are part of the Solar System Alliance's unit, "Sophia," who keep the world under the Alliance's thumb. However, this will soon change when two DOWL Masters—Aoi Saotome and Reine Ward Takajou—have a fateful meeting at a high school in an aerial city.
Perverted, cocky Ken used to live a normal life until several giant monsters crashed onto his city. In the midst of their carnage Ken’s secret crush was killed, and his grandfather seriously injured. Hope seemed lost for the inhabitants of the city and the world, until Ken discovered that he holds the key to summon the pilotable Beast-God Riger! Within the massive bio armor, Ken must now battle the invading monsters to protect Earth, and keep them from awakening a demon within the Demon Stone – a demon who will put a stop to all human life for good!