|“||I'm the true Marik, and I'm not as kind as the one you've come to know.||„|
|~ Yami Marik|
The spirit of the Millenium Rod, DarkNite was a god-like being with the power to turn mortals into cards.
Card Majin is sealed in the Forbidden Temple but is eventually unsealed by Heishinm, who he then kills.
Atem and High Priest Seto then proceed to duel Card Majin, Atem defeats him in both his normal and Nitemare forms and he is sealed away again.
Yami Marik was awakened out of Marik's hatred and anger at the Pharaoh for having to be his tombkeeper, along with Nitemare's spirit in the Millenium Rod. He took over Marik's body and imprisoned his father in the Shadow Realm, but was contained by Odion. Yami Marik did murder his father(he sent his father to the Shadow Realm in the 4Kids version), he almost did the same thing to Ishizu, but was stopped by Rishid.
When Rishid was knocked out by the Winged Dragon of Ra, Yami Marik was able to reawaken within Marik, possessing his body and trapping him inside his mind. He proceeded to duel as Marik Ishtar in the tournament.
Yami Marik's duels were all twisted Hell duels. In the quarterfinals, he dueled Mai Kujaku in Hell, in which whenever a duelist lost a monster (to an attack by their enemy), someone would be erased from their memories. Unlike Mai, Yami Marik did not mind this at all, as there was no one in his mind worth remembering. He lost the Pantomimer and Pandora the Conjurer during the duel. Mai managed to steal and summon the Winged Dragon of Ra, the most powerful of the three Egyptian God Cards, but was unable to control it, so she was defeated trapped in Hell. In the manga, the duel is even more creepy and disturbing as each contestant felt the pain caused by their loss of monsters and direct attacks as if they were real, along with illusions of blood and decapitation, and Mai was trapped in her own mind, where she would ultimately die if Yami Marik was not defeated within 24 hours.
Later this night, Yami Bakura dueled Yami Marik on the request of Marik's spirit who wanted to to regain his body. The two evil spirits dueled in the Hell, in which whenever a player lost life points, their body would vanish. Yami Marik won and Yami Bakura was trapped in Hell (though he escaped to Yugi's Millennium Puzzle). In the manga, Yami Bakura was temporarily destroyed, though the part of him inside the Millenium Puzzle allowed him to remain.
Enter the Shadow Realm
The tournament was interrupted when Noah Kaiba made the blimp land at a station where his virtual world was located in. After Noah set the virtual world to explode, Yami Marik destroyed the control center so it could not be stopped.
Battle City continued from here, and a four-way duel between Yugi, Kaiba, Katsuya Jonouchi, and Yami Marik was held to decide who would face each other in the semifinals. Yami Marik and Jonouchi both lost (as Jonouchi intended), so they dueled in the semifinals. Yami Marik took their duel to Hell, in which players would lose life energy as their monsters were destroyed. (In the manga, the contestant once again felt the pain of their monsters, just like any time Yami Marik would launch a Hell game.) Jonouchi held his own against Marik and resisted to the Winged Dragon of Ra's attack which should have reduced him to dust. Just as he was about to win, he collapsed from the energy he lost, and Yami Marik won by default. However, Joey's soul did not go to Hell (because Joey survived and only fell into a coma).
Yami Marik dueled Yami Yugi in the final round, in which both Marik and Yugi, their original selves, would disappear whenever they lost life points (either to be destroyed or trapped in Hell, following the manga or the anime). Eventually, Yami Marik's Winged Dragon of Ra was destroyed, and Marik and Yami Marik were switched around, making Yami Marik the victim. No longer evil, Marik decided to forfeit the match so the Pharaoh could fulfill his destiny. Yami Marik tried to convince him not to, but was unsuccessful, and as Marik lost the duel, Yami Marik was destroyed, and Mai released from Hell.
Waking the Dragons
An apparition of Yami Marik appeared as a lost soul alongside Bandit Keith, Pandora, the Rare Hunter, the Meikyū Brothers and the Player Killer of Darkness; as Yami was trying to get to Yugi, whose soul was taken by the Orichalcos. It is unlikely that this was really him (as opposed to some sort of illusion), however, as neither Pandora, the Meikyū Brothers, nor Keith were in Hell or taken by the Orichalcos.