It all began with the first timetraveler and the user of the first pendulum crystal: Tempus Nisell. He sought the ultimate power, dominion over past/present and future. Having been presumed dead for eons, his heirs continued his work. Fortuno, Anastasia and Amadeus; they acquired knowledge and power of their own as they walked from world to world. Endlessly they were pursued by December and his band of companions who could freely move through time with their own pendulums. In the end the sons and daughters of Tempus could only cease this chase by dividing the earth into two timelines. While their pursuers were trapped in one world, the Nisell family began conquering the other. With their knowledge they finally created the perfect global empire of Millennium and introduced an era of peace to the world.
Yet their path was not without sacrifice. Each time they returned to the past, the timeline they abandoned was destroyed with no survivors.. Except for one young girl: Alice Brandt. It was her that found Fortuno first, after he was banished from his own empire by his jealous brother Amadeus. Having lost his all memories but that of his alias, he called himself Uno. Together with Alice, her friend Eric, Iria from the Dreamworld company, Adamant the former XYZ-guild commander, and an enigmatic trio of spirits called the Prophecy Sisters: Uno managed to return to his world and to Millennium. There, reunited with his family and other friends like Dom and Zach, he slowly regained his memories and learned of his actions. Many challenges awaited him; the Guilds who desired a fusion of both worlds, the Circle who wanted to abandon one world and take over the minds of the other, Martel who used his own pendulum crystal to enslave duelists around him, and his own treacherous brother.
One by one, Uno and his friends managed to overcome them. And they even enlisted the help of December and his company. However there was one foe too great for all of them: Tempus. Uno's father had returned from death itself to reclaim what was given to his children. He was resisted. It proved fruitless. Uno, Alice, Eric and Adamant were thrown to three days in the future to witness the end of Uno's world. They could only return to the past without changing it through the gift of the oldest prophecy sister, Margot the incarnate of death. It was a hard-fought victory, which claimed Adamants life. And when Uno returned, he was sent back to the second world where he found himself alone without his friends. He only has three days before time itself will descend to purge one timeline from existence. And he has no idea where to start...