Preperation- First off make sure you have all you GF's and magic junctioned. When you junction, give one character Shiva and the draw command and the other with the magic command with Blizzard and Blizzara if you have Mid-Mag and refined Blizzards into Blizzara's and The GF Quezacotl. Have ALL Fine magic junctioned to the character that has the draw command so you don't use it. ALL FIRE MAGIC HEALS IFRIT!!!!!
Battle- I started out by using Shiva, if you have her with boost, use that to cause more damage. While the character with Shiva summons her, your other character should focus on inflicting as much damage with Blizzard and Blizzara. (If you have it- Blizzara I mean)
Higher SeeD Rank- Watch Ifrits HP when it hits around 100, then when the clock runs down to 20-25 seconds left, use Blizzard, Blizzara and physical attacks.
Don't use Quezy it's just a waste of time. (Throughout the whole battle)
Preperation- Since Seifer left your party, you want to make sure that his junctions (If you gave him any) goes to Selphie and that everyone has at least 1 GF so that you can have characters draw and heal one another. Make sure that Quezy is with the character that has the best compatibility with, you'll need it later on. Do this before the battle, right when you get Selphie you should.
Battle- This battle is very easy. Now use your drawing characters and draw some Esuna magic from Biggs stock up on that as much as you can, it junctions quite well and is useful in battles to cure negative stats. While any character should either use physical attacks until Wedge comes, when Wedge comes stock up on magic to you desire, draw Cure from Wedge to heal any of your party members and more Esuna from Biggs. While you use physical attacks or magic, save all thunder magic though. Once you've caused equal damage to both Biggs and Wedge the real Boss fight begins...
Preperation- You have no time to prepare becuase once Biggs and Wedge are blown away then he comes, just first heal all characters that have damage to them first. But before anything draw Siren from it immediately!
Battle- As I said draw Siren first thing, and then rely on powerful boosted to a max. GF's. Use one character to cure the others and to draw Double, a spell that junctions well to a few stats, and will be of great use in future battles, especially the last and final one. Avoid using any magic and just use GF's bossted to a max. like I said before and physical attacks if needed.
Preperation- Right after your battle with Elvoret and and Biggs and Wedge you have 30 minutes to get back down to the port. It may sound simple, but it's not, Biggs and Wedge let out XATM-092 a invincible machine. So right after the battle heal your characters and junction Siren to a character. Right after that go down to the first floor of the Comm. Tower and it'd be best to save your game.
Battle(s)-
You really only have to fight this son of a bitch once, all the other times are completely avoidable. Now when you first fight it summon Quezacotl (Quezy) right away, while you other characters plummel it with Thunder magic, and if only one has Thunder magic, one has Quezy, draw from it or better yet to save time summon any GF except Siren so that you can boost them if possible. If you can't boost your GFs, keep using Thunder magic, Quezy and your BEST GF's. Even though this machine is invincible, it falls when that happens excape from it by pressing L2 and R2 until it says got away or whatever it says. Keep running from that. Now, there are several tricky spots that you can avoid fighting it.
The Cliff- Use the D-Pad control, it will automatically get your character around it. And keep MOVING!
Moutain Path- Walk halfway down the steep moutain path so you're not vulnerable to it's large steps, then run the rest of the way down the path and again... KEEP MOVING!
The Bridge you crossed earlier- XATM-092 will jump over your party leading an attempt to cut you off, when this takes place run or walk the other direction but not to far then turn around and continue going to the transport, KEEP MOVING FAST! You can only afford to fight this thing a min. amount of times.
Preperation- Make sure that Quistis gets her junctions back first of all. Make sure both of your characters are healed and that they have all their commands back. Do that before heading into battle of course.
Battle- When you head into battle you'll have three Raldos' eliminate them first, have the character with Draw stock up on Protect and Shell and have the other use GF's, once you can't draw anymore or you don't want to just beat them into submission using attack magic and GF's. But try and kill the Raldos' first becuase if you don't and kill the Granaldos they'll beat you with their amazing speed. For the Granaldo just use it's own magic against it and beat it with attack magic.
Preperation- Just make sure your characters are healed with all their junctions with GF's that are compatible with them, good magic and lots of cure spells. Also make sure that you've saved the game before going into this battle.
Battle- Right after you use the magic lamp you will fall into another dimension and hurdled right into a battle with Diablos. First start off by summoning GF's leaving a drawing character to stock up on Demi or use it against him, which may be the strongest attack against it right now. When the GF uses Gravija leaving your pary with 1/4 of HP left, have Squall and Zell use their limit breaks first then have Selphie use her limit break slot. Make sure you use Full cure though, it may not pop up the first time so press "Do over" until you get it then use that and continue plummling him with physical attacks, drawing Demi and casting it on him and GF's and attack magic also. When you beat him he will become your new GF to junction and fight with.
Preperation- Make sure you have a few Pheonix Downs, Remedy's or Esuna magic. Someone with the draw command in case you need to draw Esuna and a person with the magic command and Esuna. And everyone with the item command so you can revive anyone with Pheonix Downs or cast a Pheonix down on Geragero (The second form).
Battle- The Fake Pres. may seem quite hard, but he's really not. Just simply use Physical attacks and one or two boosted GF's. For Geragero, just used a Pheonix Down or Elixer or summon Ifrit and use Fire magic. If a negative stat gets on a character don't leave it. Draw Esuna use a Remedy or use Esuna from stocked magic.
Preperation- You first encounter just Sacred, fight him, make sure you have Float spells, they'll come in handy in this and the next fight. Keep your HP up.
Battle- Sacred only- Cast float on him and protect of shell on you to cut down on his powerful physical attacks. Now just simply unload with GF's and physical attacks and he'll run off.
Battle- Sacred AND Minotuar- Like before cast Float on him and Minotuar and cast it on your party also. Also cast Protect or Shell on your party too to cut down on damage, after that just focus on beating them into submission with GF's and physical attacks. Just make sure to keep your HP up. And if you have the draw command, use it and draw protect or shell they're oth pretty good magic.
Preperation- Nothing really just have Esuna Magic, Draw command and item command for Remedy's if you don't have Esuna Magic.
Battle- Draw the GF Carbuncle RIGHT AWAY, before anything. Now just use a simple boosted GF except Ifrit and that should be good to go.