Bahamut is the King of the Dragons in the original Final Fantasy. He lives in a subterranean network underneath the Cardia Islands, and grants the class change to the Warriors of Light after they bring back a token of their courage from the Citadel of Trials.
In the Soul of Chaos, there is a Dark Bahamut in the Lifespring Grotto. Like the version that changes the player characters' class, Dark Bahamut sets the party on a trial. Dark Bahamut's trial is to slay a certain number of specific colors of dragon from his underlings, and the reward is that he will open the door and let the party out of the room. The quest can be completed by killing all of the dragons in the room without concern for their color.
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Bahamut's Nintendo Power artwork.
Artwork of Bahamut and the Warriors of Light from the Nintendo Power strategy guide.
Bahamut in the NES version.
Bahamut in the Wonderswan, PS1, GBA, and Mobile remakes.
Dark Bahamut in the PSP remake.
