Hello everyone!!
I have a couple of questions,and I thought that you guys could help me out.
I'm currently on the 3rd disc of the game and I got a little stuck:
1)where and how can I fight Bahamut,so that I can have him as a GF?
2)How do I make Doomtrain?
3)How can I find the items to make Lionheart?

Thanks to anyone who answearsO:]

1.)
Anyway, now for one of the toughest sections of the game; head to Edea's
House and head due west from there, and you should find the Deep Sea
Research Center sitting out to sea, all by itself. Upon landing on it, if
Zell's in your party, he'll tell you what little he knows about this
place. Make your party, preferrably Squall, Zell and Quistis, and
junction Sleep to two of the character's St-Atk-J, and Blind on the third
character; Blizzaga to their Elem-Atk-J, Ultima to their Str stats,
Meltdown to their Vit stats, Death to their St-Def-J, and Firaga, Holy,
Quake and Thundaga to their Elem-Def-J.

Enter the building and you'll see a bright pillar in the center of the
room. When the pillar brightens up, don't move or you'll get into a
random fight; move towards the pillar whenever it's in its gloomy stage.
When you get close enough, a voice will talk to you; pick the second
option, "It's not our will to fight," and you'll get into a battle with a
Ruby Dragon. Smack it with a normal attack to put it to sleep and then
summon Doomtrain. Draw whatever you need from it and then mug it, before
beating it to death. Once more the voice will speak to you; pick the
second option, "Never," and you'll get into a fight with yet another Ruby
Dragon, but this time it will be a Back Attack, unless you have Cerberus'
Alert equipped. I didn't and it started with Breath before I could turn
around, and since Breath is a physical attack, the damage was doubled,
killing my entire party at once. Just repeat the tactic from last time to
dispatch it. The voice will speak one more time; pick the hidden third
option, "It's our nature," and the speaker will show itself!

===BOSS: Bahamut===========================
DRAW: Flare, Curaga, Full-Life

Start the fight by smacking it with the attack of whoever has Blind
junctioned to their St-Atk-J, to blind Bahamut, rendering him nearly
useless, and then follow it up by summoning both Cerberus and Doomtrain.
Triple Aura onto the party, and if Quistis has learnt it, use Mighty
Guard to defend against Bahamut's Mega Flare, or just triple shell onto
the party. Pummel Bahamut with Renzokuken and Armageddon Fist, while you
have Quistis draw any spells necessary. This shouldn't take too long to
finish off. As a note, Squall's Renzokuken looks absolutely awesome in
this fight, the way he jumps up onto Bahamut's wings XD

WIN: Hyper Wrist, Bahamut Card, Bahamut (GF)
MUG: Hyper Wrist

2.) Find the Solomon Ring at Tears Point, and get six Marlboro Tantacles, six Remedy+ (refined from normal Remedies), and six Steel Pipes. Then just use the Ring anywhere.

3.) You need an Adamantine (either aquired by mugging the BGH251F2 at FH or killing Adamantoises. You can also refine the Minotaur card to get ten of them.), four Dragon Fangs (dropped by Blue Dragons), and 12 Pulse Ammo (refined using Ammo-RF. One Energy Crystal refines into ten Pulse Ammo, and one Laser Cannon refines into five Pulse Ammo). You won't need the weapon magazine if you have all of the required items when you go to a weapons shop.

1- Deep Sea Research Facility, in the very bottom corner of the WM
2- 6 steel pipes, 6 marlbro tentacles, 6 remedy+ iirc
3- Energy Crystal: Refine 10 Elnolye cards, don't remember the rest, consult a FAQ.

I always thought the process in getting Doomtrain was a little confusing. They never really tell you how to get it.

Thanks for the reply's,no I got 1 more question:
how do I get the steel pipes??

iirc, you can refine them from Elastoid cards.

I don't have any Elastoid cards,isn't there any other way?

They aren't that hard to win, keep playing cards and you'll them sooner or later.

Just steal/win some from the Wendigos in the redish colored area near the Galabdian Missile Base and Desert Prison.