Preparation is pretty simple, unless you like to be stylish or show-off-like. Basically, just be sure to have everything on my checklist. It doesn't matter who you use, however, I find it preferable to have Squall, Quistis, and Rinoa in the team. Here's my checklist:
|Defend||Equip on as many people as you can. This ability is required|
|Revive||Equip on as many people as you can|
|Meltdown||You should already have some; if not... get some!|
|Doomtrain||No Meltdown? Use Doomtrain instead|
|Megalixirs/Mega Potions||If you've got Vit and Spr of about 110, you'll want Megalixirs. More than that, and you should only need Mega Potions|
|Aura||See the note on Meltdown|
|Lionheart||See the note on Meltdown|
|Wishing Star||Only if you intend to use Rinoa|
|300x Death||If your characters are at a level that is a multiple of 5, you'll NEED to equip 100x Death to their ST-Def-J|
|9999 Max HP||Probably the most important thing to have. Omega uses a move called Medigo Flame that deals exactly 9998 damage, so having 9999 HP for all characters would be a good thing|
|Speed||Omega Weapon has a speed of 61, so with speed stats over double that for all of your party, you can get in SIX attacks before Omega does ONE.|
|Battle type set to Wait||This means you can get your attacks out a lot faster against Omega|
Alright, given that checklist, you should be okay. Here's what my battle menus would look like:
Rinoa has her final command as "Revive/Item" since only 1 GF naturally comes with Revive. Assuming you've gotten all GF's and all abilities learned and stuff, you can get another GF with Revive, but it'll require a bit of cash. To teach a GF Revive, you must have a Phoenix Spirit. To get a Phoenix Spirit, you can follow this flowchart...
3000 Phoenix Downs --(Med LV Up)--> 60 Mega Phoenixes --(Tool-RF)--> 20 Phoenix Pinions --(GFAbl Med-RF)--> Phoenix Spirit
You can pick up where you need to in the chart, dependent upon your current inventory, but the simplest way (In terms of item rarity) to get it is to refine 3000 Phoenix Downs. If you don't have the cash or supplies for that, just give Rinoa Recover (Or Doomtrain if you don't have any friggin' Meltdown magic.).
Now then, with that aside, let's get to...
THE EPIC BATTLE!
Alright, I'm assuming you know how to get Omega to come out. So, let's get to the battle itself. Omega will open with his almighty Lv.5 Death spell. Hopefully, that went right through you; I'll just assume it did. Now, this's what most people don't seem to realize. Omega attacks in a certain pattern. Every time. It doesn't matter what, it's the same attack pattern. That is why he is so friggin' easy. So, instead of giving you a turn-by-turn strategy, I'll just give a generic strategy. Here's the order of attacks, what the attacks do, and other random notes:
1. Meteor - Causes a bit of damage to all. BE SURE TO HEAL COMPLETELY SOON AFTER!
2. Medigo Flame - Causes 9998 damage to all, no matter what.
3. Gravija - Takes 3/4 of current HP. Defending is highly recommended after this move.
4. Terra Break - A physically-based attack like Meteor. Except on some super steroids.
As far as I know, the only way to not die from this attack is to Defend (About 110 Vitality for someone resulted in 4000+ damage, per hit. Ouch.).
5. Ultima - Causes some good damage if lacking in Defense.
6. Light Pillar - Causes 9999 damage to one person. Basically, a totally unblockable instant death move.
And that's basically it. Basically. He'll also randomly do some physical attacks in between those signature attacks (Average Vit of around 100 will result in one taking about 3500 HP damage.). If you need to get healed before the next move and he does this, simply re-heal. But, other than that, that's all you've gotta worry about. The best time to deal damage is in between Light Pillar and Meteor and also in between Gravija and Terra Break. Just give him what you got, particularly in between those two attacks, and he'll go down, easy as apple pie.