Daimon

Daimon is honorable, perceptive and deeply loyal to Kaiba. His loyalty differs from simple obedience: he remembers Kaiba as a kinder child and believes that part of his personality still exists beneath the ruthless person he has become.

He takes pride in games and refuses to compromise the integrity of his duel. Although Kaiba provides equipment that would allow Daimon to see Yugi's hand, Daimon refuses to use it.

His physical condition leaves him frail, but he remains determined to fulfill his role as a Game Master. His greatest concern is not defeating Yugi for its own sake, but finding someone capable of reaching Kaiba emotionally.

Daimon uses a Zombiemaster Deck. His strategy deliberately allows weaker monsters to be destroyed, increasing the strength available to Zombiemaster when it enters play.

He demonstrates considerable skill and experience, defeating Yugi in their initial game before facing Dark Yugi. His understanding of both people and cards allows him to recognize the difference in demeanor when Yugi's other personality takes control.

Daimon depends on a life-support capsule and can remain outside it only for limited periods. Kaiba supplies a mobile system that supports him during his duel.

Daimon serves as the fourth and final member of Kaiba's Four Game Masters. Kaiba releases him from his medical capsule and arranges a situation that forces Yugi into a game at Kaiba Land.

The confrontation places Anzu Mazaki in danger from a mechanical dragon, prompting Dark Yugi to emerge and continue the duel.

Daimon is defeated after Dark Yugi turns the logic of his Zombiemaster strategy against him. Afterward, he asks Yugi to restore the kindness that he believes still exists within Kaiba.

Seto Kaiba is Daimon's employer and someone he has known since Seto Kaiba's childhood. Daimon remembers the kindness Seto Kaiba once showed him and continues believing that side of him can return.

Yugi Mutou becomes Daimon's opponent as part of Seto Kaiba's campaign against him. Daimon comes to respect Yugi Mutou and entrusts him with the hope of reaching Seto Kaiba.

Anzu Mazaki is placed in danger as part of the circumstances designed to force Yugi Mutou into Daimon's game.

Ridley Sheldon, Ryuichi Fuwa and Aileen Rao are Daimon's fellow members of the Four Game Masters.