I'm stuck on the part where you're at Mt. Gagazet, you have to fight Seymour. I always die! I can't do it, and neither can my best friend. Any tips?

Yeah, Seymour Flux and Mortiorchis can be a tough battle if you don't know what you are doing. But try this:

During the battle, Tidus, Yuna, and Kimahri will all have Trigger Commands that will allow them to talk to Seymour. This will allow them to raise their Strength or Magic Defense.

Of course, start the battle out by having Tidus cast Hastega, since he may be the only one that currently knows the spell. Next, let Yuna cast Protect on your party, reducing the physical damage by half. However, there is one bad thing; Seymour will occasionally cast Dispel on the group, so you would have to waste turns to casts the spells all over again.

One attack that is dangerous is Cross Cleave, which usually takes about 2,500 HP from the entire party. That is why you want to have Protect cast on all three, so you will only receive half the damage.

If you notice carefully, Seymour has an attack pattern that he abides by. He will use Lance of Atrophy, inflicting Zombie on one of your party members. As soon as you have the opportunity, use Holy Water on the Zombified character. If you don't use it before Seymour's next turn, he will then cast Full-Life on that character, greatly reducing their HP, and sometimes killing him/her.

Casting Silence and Bio on Seymour certainly doesn't hurt either, as they could block him from using magic and maintaining his current HP.

This is where you need to be sharp. During some point in the battle, Mortiorchis will begin to charge up the Total Annihilation attack, and will use it in either two or three turns. Once it begins the charge, you need to have one of your characters attack it and deplete all of it's HP. By doing this, Mortiorchis will suck more HP out of Seymour, and it delays the Total Annihilation attack for a little bit. I would recommend using Auron or Lulu to perform this attack.

At about this same time, Seymour will start casting Flare. So, it would be very wise to cast Shell on the party.

If Mortiorchis performs the Total Annihilation attack, you will probably have a major ammount of HP gone. So, just use a Mega-Potion to cure yourself.

You can avoid the Total Annihilation attack by bringing in one of your Aeons on the turn before Mortiorchis performs it. It may be cold to let Valefor or Ifrit take the fall, but it's better than a game over.

Oh my gawd, thank you so much. I was totally clueless on how to get past that stupid freak. You are a big help!