Blue-Eyes White Dragon was the monster ka spirit of Kisara, although it only emerged while she was in an unconscious state.
With Kisara captured, Aknadin heard of the Dragon's power and hoped to transfer the ka to his son Seto, unconcerned that this would mean killing its current host. The imprisoned Kisara was unaware of her ka and thus unable to summon it. Seto, disgusted at the idea of using her without regard to her life, attempted to save her. He failed, and both their lives fell into danger. However, Kisara lost consciousness, causing the White Dragon to emerge and ultimately resulting in their rescue.
Seto had come to care deeply for Kisara during this time. He defended her until her death at the hands of Aknadin, who proceeded to possess his son. Perhaps showing that she felt the same about him, Kisara's spirit entered Seto's mind and destroyed Aknadin, freeing the young priest. Afterwards, Seto extracted the White Dragon ka and used it to fight Zorc Necrophades.
According to Takahashi, Seto's feelings for Kisara are the reason behind Seto Kaiba's modern-day obsession with the Blue-Eyes White Dragon.
In the manga and first series anime, Seto Kaiba stole Sugoroku Mutou's "Blue-Eyes White Dragon" card. Soon after, Dark Yugi faced Kaiba in a Shadow Game of Duel Monsters to get the card back. Realizing he would otherwise lose, Kaiba slipped the card from his sleeve into his hand and summoned it. Since it was a Shadow Game, the spirit of Blue-Eyes White Dragon was summoned. However, its heart did not lie with Kaiba, so it destroyed itself, allowing Yugi to revive it with "Monster Reborn" and defeat Kaiba. (In the anime, the Duel was a draw).[1][2]
In Yu-Gi-Oh! Ultimate Masters: World Championship 2006, Blue-Eyes White Dragon uses a Deck titled, "March 2004 Deck". This character was a Limited Duel Duelist and this deck refer to March 2004 Forbidden & Limited Cards List.
In Yu-Gi-Oh! 5D's World Championship 2010: Reverse of Arcadia, Blue-Eyes White Dragon and Red Eyes B. Dragon can be unlocked as Tag Duel opponents by defeating Tag Team Love Reptiles? 3 times. Their Tag Team name is Legend's Anniversary.
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Added by Deltaneos
