Location
	Once you find the Deep Sea Research Facility on disk 3, you can face and defeat Bahamut. He will then join your party as a GF.

Bahamut
	Elemental: None
	Attack: Mega Flare
	LEVEL		HP		ATK. POWER
	1		-		-
	10		-		-
	20		-		-
	35		3274		1451
	40		3714		1614
	50		4600		1940
	60		5494		2266
	70		6396		2593
	80		7306		2919
	90		8224		3245
	100		9150		3571

Ability	AP	Opens		Ability	AP	Opens
Ability x4	Learned	None		Rare Item	250	None
Magic	Learned	None		SUMMAG+10%	40	SUMMAG+20%
GF	Learned	None		SUMMAG+20%	70	SUMMAG+30%
Draw	Learned	None		SUMMAG+30%	140	SUMMAG+40%
Item	Learned	None		SUMMAG+40%	200	None
STR+60%	Learned	None		GFHP+10%	40	GFHP+20%
MAG+60%	Learned	None		GFHP+20%	70	GFHP+30%
Mug	200	None		GFHP+30%	140	GFHP+40%
Move-HP up	200	None		GFHP+40%	200	None
Auto-Protect	250	None		Boost	10	None
Expendx2-1	250	None		Forbid MAG-RF	Learned	None

The lord of dragons has returned again in Final Fantasy VIII. Bahamut's attack is one of the few non-elemental GF attacks, but it is not as powerful as in previous games. That said, the animation is long enough to give a boost to 250 for extra damage.
Above and beyond, Bahamut's best offering is the Ability x4. This is the only GF to have it. You must find the two Rosetta Stones, and teach any other GF the ability. This alone makes getting Bahamut worth while.
Bahamut also has a few useful abilities to hand out. There is another Mug, as well as a Rare Item. With the Rare Item, you will have a higher success in stealing the harder to get items from your enemies.
FORBID MAG-REF allows you to refine items into Meteor, and Ultima.