|Age||Over 3000 Years|
|Voiced by||Dan Green|
Yami Yugi, known as Dark Yugi in the manga and Japanese versions is the spirit of Pharaoh Atem that has been sealed in the Millennium Puzzle.
After Yugi Muto solved the Millennium Puzzle, Yami Yugi resided in Yugi's body and would take possession of it when Yugi or his friends were in danger. After Yugi became fully aware of Yami's existence, Yugi could voluntarily give control of his body to Yami.
In the manga, Dark Yugi starts out as an unforgiving vigilante. He emerges to deal justice to people who trespass the souls of Yugi and his friends. Although his acts are righteous, his punishment Penalty Games are usually brutal. These are toned down in the first series anime, as most of them are made illusions. In the first episode of the English anime, Yami defeats Seto Kaiba and uses his power to break his mind. Kaiba is able to recover.
He is slightly reserved, as he doesn't reveal his existence to Yugi or his friends. After Yugi admits to thinking "another Yugi" exists inside him, his friends become aware of his existence and accept him as a friend.
Yami's pride is his greatest strength and weakness. Initially he refuses to lose games, without considering the consequences. This has caused him to almost kill Seto Kaiba by attacking him while he stood on a ledge and would fall if his monster was attacked and Yugi won the duel. Yugi holds him back from such acts at times, although not always successful. Yugi becomes afraid to let Yami out for a while, because of the harm he could cause. Learning how to lose becomes an essential part of Yami's journey, which is tested in the Ceremonial Battle.
Yami is also wise and intelligent knowing all the rules and details of how the game is played. Yami is also capable of reading the ancient language of the Egyptian rather they are riddles or clues figuring out what they mean.
Through Yugi and his friends, Yami Yugi learns the values and powers of friendship and unity. After seeing Yugi overcome Marik in his Duel with Joey, who has been possessed, Yami thinks to himself, he learned something from Yugi; that in kindness lies the greatest strength of all; one day Yugi will surpass him in every way.
Atem is an ancient Egyptian Pharaoh who sealed his soul within the Millennium Puzzle. His soul took on the entity Yami Yugi, which resided in the body of Yugi Muto, after Yugi solved the Millennium Puzzle.
As son of king Aknamkanon, Atem became heir to the throne and the Millennium Puzzle. During his childhood he befriended Mana and was protected by Mahad at times.
Atem defeated Zorc Necrophades by using a spell which included his name, he then sealed Zorc in the Millennium Ring. He then sealed himself within the Millennium Puzzle, erasing his mind in the process to keep the spell from ever being used to resurrect Zorc. The Millennium Puzzle was shattered and sealed within his tomb.