Run up and you will later encounter Seymour Kelk Ronso. After much talk they let you through, but save your game first.
Use the Lancet attack often to acquire the abilities you don’t have. Each time you use Lancet and acquire an attack you don’t have will initiate your Overdrive. But you must successfully learn a new ability. When the two brothers are together use Lancet, otherwise each of them will block your attacks and significantly reducing the damage to single digits. When they use Bulldoze they will move to opposite ends or closer to each other. Use Thrust Kick if you can. Also try to knock both of them to about 200 HP without killing them, this way when you knock one out the other will cast Berserk, but you can kill them more instantly. You can learn Mighty Guard(arguably the best defensive spell in the game) only after one of the brothers has used Mighty Guard. Use HiPotions to heal yourself and if you did make Kimahri a magic user, have him use Watera or Fira against the two.
I remind you that it’s very tough from here on out. Getting through this mountain is tough, make sure to boost your stats. When you make it to the next save point(which is pretty close, but since the game’s rate of encounter is so high, it’s a long way) make sure to build your Overdrives for your summons and for your characters(or whichever Overdrive you find useful). Don’t use them until you finally reach the next boss though, you’ll definately need it.
Seymour Flux, Mortiorchis
Now be prepared for a tough battle. Cast protect, Haste, and Shell on every party member available, or at least every party member that can mean something to you in this battle. Use all your Overdrives that you have been saving up and talk with Seymour to boost stats. The Cross Cleave attack is the attack to watch for. Seymour will sometimes cast Dispel on all party members before using it, thus nullifying Protect. The Cross Cleave can deal up to 3000 HP of damage against weaker characters and about 2000 to the more durable characters. Unless you’ve been stat boosting like crazy, chances are you won’t survive after this. Use Bio on Seymour, though sometimes it may not connect since he is highly resistant to the magic attack, but be persistant in it. It’ll be the key to your victory. Watch for Antropy that puts one of your characters in Zombie Status…use a Holy Water, Remedy, or Esuna to heal that character…otherwise the character will die from the cast of Full-Life.
Now depending on how you leveled up Kimahri and where you had placed him on the Sphere Grid can make Kimahri barely useless, or incredibly useful. My Kimahri did about 3700 HP of damage per attack after talking with Seymour, but I also used the Friend Sphere to move him into Auron’s grid area. I highly suggest that you level up before coming back and trying again if you lose. Chances are that you lost because you were too weak rather than lack of good decision making. Keep casting Haste and Protect on all party members, it’s a must…even if Seymour does nullify the attack. Cast Dispel(if you have it, otherwise shame on you) on Seymour when he casts Protect and watch for your summons…they’ll be banished everytime you bring them into battle…but your main goal is to use them for their Overdrives and nothing else. Use Diamond Dust twice if you can, it always deal 9999 damage. If any of your characters are strong enough, you can keep attacking Mortiorchis, and assuming you do over 4000 HP of damage(like my Auron does, or Kimahri when he talks with Seymour), you can make this a quick battle…but be sure to always keep Protect up.
When the Mortiorchis starts to attack on its own, take it down immediately to disrupt the attacks. Watch for the Total Annihilation attack, it hits about 20x(I didn’t bother to count) and each hit does about 400-800 HP of damage. Having Protect will help greatly. When Rikku’s Mix is available, combine the Lunar Curtain and Light Curtain to give the party Super Mighty G. Protective spells play a huge roll in this battle, and so does using all of your Aeon’s overdrives. If you can successfully connect with all 5 of your Aeons’ Overdrives, then you’ve pretty much won the battle. You should do about 45000 HP worth of damage to Seymour, which is actually a little more than that each time since Mortiorchis drains 4000, 3000, 2000, and then 1000 HP consecutively for the remainder of the battle. So that is about 55000 HP of damage, and if both your Kimahri and Auron can do at least 3000 a piece before Protect is cast on Seymour, that’s 61000. So all you have to worry about is just 9000 HP worth of damage…easier said then done but eh, I’ve done it. =D Also cast Dispel when he casts Protect.
Now go and save your game. I’m assuming most of you wouldn’t want to fight this boss again. Now you’ll soon control Tidus in Zanarkand, head for the boat and go inside the cabin…you’ll hear some spooky news inside, follow Fayth out and talk with him/her. When you wake up, head around…but flee for the enemies before you reach the save point, they just get tougher and tougher.
Now when you reach the save point you’ll encounter a fork in the road. Note that you can’t get the Return Sphere and Recovery ring unless you complete the trials, so you’ll have to get the Lvl.1 Key Sphere first prior. The path at the top left is the way forward, but from the right of the save point pick up a Return Sphere and Recovery Ring, and at the very top to the right is a Lvl.1 Key Sphere(I know some of you will need it). However, the gaping ditch won’t let you proceed upwards…so go left and around(yes, you’ll need to).
You will eventually have Wakka, Rikku, and Tidus swim underwater without the rest of the party. For me, it’s my weakest group…what a coincidink huh? Swim ahead and you will eventually reach the first trial of Gagazet. You will have to hit the glowing sphere with Wakka’s blitzball…it’s not too hard…just wait for an opening and bam! You’ve got it. Now swim back to your party and go back to the save point.
There are a set of stairs that replaced the ditch earlier. Head up top as you cannot head right(probably a hidden canyon). You’ll reach three glowing orbs, have Rikku go for the green, have Tidus go for the blue, and Wakka for the red. Now go back to those lights and pick up the treasure chest, and in case you might have forgotten, press O to submerge. Go back to the area that was previously cut off and pick up the items that I told you earlier about.
Now save your game and head to the left…and be prepared. Note, I’m not too sure about this and I will need some verification, but I’ve received a Pep Talk instead of a Star Armguard, or the other way around. I’m not sure why this is…but eh. Take the stairs up past the save point and go left and walk through the rock path.
This battle will be tough. Your first task is to cast Reflect on the boss immediately…then call out Shiva. Make sure to cast Esuna on your characters to heal the status effects. Though using your Overdrives won’t be possible in this battle if you’ve been hit with the Photon Wings. Put up Mighty Guard or Super Mighty G if possible. Each time you use an Overdrive the Santuary Keeper will counter with Curaga…which heals back any damage you might have dealt it…sometimes. The key to winning this battle is Reflect, otherwise you don’t stand a chance. Note that your Aeons can be inflicted with the Curse status as well. This boss is smart though, it’ll cast Reflect on your Aeons and then heal itself by casting Reflect on you. Unless you have the Dispel spell for your Aeon, chances are you won’t be able to counter it. Now remember that you have Reflect casted on the boss, so cast Reflect on yourself and then use the intended magic attack on yourself to damage the boss. Bio works well in this battle too. Use Armor Break to break down it’s defense, use Shell to guard against the Mana attack, and Power Break and Magic Break also works well. This boss will build your Overdrives fast, depending on what Overdrive mode you are in. When it casts Regen, use Dispel. Then make sure to cast Reflect back on the boss afterwards. If you can cast Bio, Dispel, and Reflect…you are in good shape to win this battle.
Go back and save your game and continue on. After a short event arises, check the sphere that had dropped. This refers back earlier to the game, when Tidus had cut off Yuna…now you see why. You’ll later witness Deja Vu and finally understand the meaning of the game’s intro.