ATTACK: MEGA FLARE
HOW TO GET:
Go to the Deep Sea Research center. It is near the bottom left corner of the map.Walk to the glowing cylinder and examine it. Bahamut will ask youthree questions, the answers are 1.The only option.2."Never" 3.There is a hidden reply below the rest. Ifyou answer correctly, you will have to fight Ruby Dragons, andthe way I was told to kill them was use Tonberry's lvl downskill, and then attack a few times. If you wait a while before going to the Research Laboratory and get some levels up and some Aura magic on the Islands Closest to Heaven and Hell, you can easily defeat Bahamut by equippingyour two party members besides Squall with revive and recover (GF skills) and repeatedly casting Aura on Squall. Just keep doing Renzokuken on Bahamut and healing Squall with recover and Bahamut will be KO'd in no time.
