Quote Originally Posted by Christmas
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Oh yeah, that thread! Good times.

To reiterate my position, they resemble each other superficially: essentially repaints of the same design, both have attacks with Flare.

However, I also suggested it was unlikely mainly because traditionally Bahamut and Tiamat have been portrayed as separate beings in other FF's. Most incarnations of Tiamat look like hydras, with multiple heads. I'm guessing the character designers just got lazy this time.