Yuugi is a somewhat frail young boy who happens to be a big fan of gaming of any kind. But when he solves an ancient egyptian puzzle he is granted all the powers of darkness. Now when confronted with danger and injustice, he transforms into a much darker and dangerous form, and proceeds to dish out the justice and punishment for those who so richly deserve it. 
(Source: AnimeNfo)

"Blue Eyes White Dragon will bring victory" while "Red Eyes Black Dragon will bring the potential of victory". A shy duelist stumbles upon the legendary Red Eyes Black Dragon, with that card in his possession, he must learn to bring out his confidence to duel.
 
(Source: Anime News Network)

10th grader Yugi spent most of his time alone playing games--until he solved the Millennium Puzzle, a mysterious Egyptian artifact! Possessed by the puzzle, Yugi becomes Yu-Gi-Oh, the King of Games, and challenges evil-doers to the Shadow Games--weird games with high stakes and high risks! These graphic novels contain new stories not seen in the anime, including the origin of Yugi and his friends!
 
(Source: VIZ Media)
 
Notes: 
- The VIZ Media release split the series into three parts with separate chapter/volume counts. "Yu-Gi-Oh!" includes volumes 1-7, "Yu-Gi-Oh!: Duelist" includes volumes 8-31, and "Yu-Gi-Oh!: Millennium World" includes volumes 32-38. 
- The final chapter of VIZ Media's "Yu-Gi-Oh!" was moved from its final volume to the first volume of "Yu-Gi-Oh!: Duelist."

Yu-Gi-Oh! Duel Monsters centers around the journey of the spirit of an ancient Egyptian pharaoh who is trying to re-discover who he was many years ago, since he has lost his memories. With the help of a boy, Yugi Mutou, the one who awakened the spirit, and his friends, he battles many villains and adversaries. Many of the villains have been linked to the Nameless Pharaoh's past, due to the Millennium Puzzle he holds and many try to take the puzzle and his power away from him. 
The series focuses on the card game aspect of it and the main theme represented throughout the series is friendship.

Set six months after the events of the original Yu-Gi-Oh! manga, Yugi Muto and his friends are in their final year of high school and are talking about what they will do in the future. Meanwhile, Seto Kaiba has commissioned an excavation to retrieve the disassembled Millennium Puzzle from the ruins of the Millennium chamber. The item had previously housed the soul of his rival, Atem, whom he hopes to revive in order to settle their score. The excavation is interrupted by a mysterious man, who faces Kaiba in a game of Duel Monsters and steals two pieces of the recovered Puzzle. What is his ulterior motive? The stakes have never been higher; the rivalries never as fierce; the risks never so great. 
 
(Source: Wikipedia)

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