Mokuba Kaiba

The Yu-Gi-Oh! series features an extensive cast of characters created by Kazuki Takahashi. The series takes place in a fictional city in Japan called Domino City, in which most of the characters that appear in the series originate. Many plot elements are also influenced by Egypt and Egyptian mythology, and as such, Egyptian characters also appear within the story.

The original manga of Yu-Gi-Oh! tells the tale of Yugi Mutou, a timid young boy who loves all sorts of games, but is often bullied around. One day, he solves an ancient artifact known as the Millennium Puzzle, causing his body to play host to a mysterious spirit with the personality of a gambler. From that moment onwards, whenever Yugi or one of his friends is threatened by those with darkness in their hearts, this "Dark Yugi" shows himself and challenges them to dangerous "Shadow Games" which reveal the true nature of someone's heart, the losers of these contests often being subjected to a dark punishment called a "Penalty Game". As the series progresses, Yugi and his friends (Katsuya Jonouchi, Anzu Mazaki, Hiroto Honda, Miho Nosaka (in the 1998 series), and later Ryo Bakura) learn that this other Yugi inside of his puzzle is actually the spirit of a nameless Pharaoh from Egyptian times who had lost his memories. As Yugi and his companions attempt to help the Pharaoh regain his memories, they find themselves going through many trials as they wager their lives facing off against others that wield the mysterious Millennium Items and the dark power of the Shadow Games.

The Japanese names in Western order (given name before family name) and English manga names are listed first and the English anime names are listed second, when applicable.

During the Millennium World story arc, Dark Yugi journeys into his lost memories and meets old acquaintances from Ancient Egypt as NPCs (non player characters) within Dark Bakura's ultimate tabletop role-playing game, the Shadow RPG (闇のＲ・Ｐ・Ｇ, Yami no Ā Pī Jī), a campaign based on the past. The Six High Priests (六神官, Roku Shinkan) protect the seven Millennium Items with their lives and have to swear eternal loyalty to the Pharaoh, Atem (serving as the player character of Dark Yugi, Atem's spirit in modern times). In the age where Shadow Games were used to determine a person's fate, these Priests used the Millennium Items and sorcery to pull out and seal human souls (Ka), which take the form of Monsters Spirits, into stone slabs to do battle; usually from criminals and those who pilfer from the tombs of the Pharaohs. Within the RPG, each characters' health and magic were represented by their Ba Gauge.

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