Final Fantasy 12

Dispel his Haste effect, then start pounding. Gabranth is able to cast the Renew spell after taking a certain amount of damage. By doing so he actually becomes more powerful. Offset his new attacks by casting Protectga to lessen the damage to your entire party. Once again, this fight is far too similar to previous Judge battles for you to really be unprepared.

The first incarnation of Vayne is a physical brawler. He will use a lot of very cinematic attacks, but for all his theatrics, he seems to have difficulty actually finishing you off. This is especially true if you protect your party with Protectga Magick.

Physical attacks are more than adequate to beat Vayne. His HP in this form is quite low and this battle serves mostly as an "introduction" if you will to the coming fights.

Now it starts to get hard. Start by Dispelling all the powerful buffs Vayne begins with and then send your entire party after him. Obviously the two schools of thought question whether it is best to focus on him, or eliminate his swords. I found it somewhat unnecessary to destroy the swords and instead chose to focus on him, but you might think otherwise.

Gabranth with inevitably focus mostly on the swords. You can ignore him. Keep hitting Vayne as hard as you possibly can and be ready to Curaja constantly. You need to keep you MP up so try to rotate the Curajas between party members if you can.

After each of Vayne speeches you might want to check him again, his Protect, Shell and Haste will periodically reappear and need to be Dispelled. If you can keep those off him you can drastically increase your chances of winning. He doesn't have any weaknesses to exploit, and he raises a Magick shield half way through, so it's physical attacks all the way. Before using items, remember the most difficult battle is still to come.

The lack of HP bar for this boss makes the fight not only difficult, but confusing. You never really know what's going on unless you pay attention. The Undying will give clues as to its HP level by its shielding actions.

When the boss is half dead it will bring up a shield that protects it from physical attacks. You'll have to move on to Magick at this point. Flare, Holy, whatever you've got. The shield wears off after a period of time so don't feel obligated to waste all your Magick.

Here's something you can do during this time: cast Protectga, Shellga and Bubble on every member of your party. That will give you a huge advantage. Another thing to do is to keep an eye out for when the boss casts spells like Faith and Bravery. Use Dispel Magick when this happens, otherwise the boss' attacks are going to increase in power by quite a bit.

The majority of The Undying's attacks are big epic-looking explosion-esque blasts that just... do damage to every member of your party. With the scope of the spell animations you might expect it to tear a hole in the fabric of space, but no, you're basically just looking at about 1000 - 2000 damage to every party member. Nothing much if you cast Bubble, and especially so if you have Curaja Gambits on everyone.

Here's something very important to keep in mind: the game is over, you are done, and there is absolutely NO reason to hang onto ANY item in your inventory. Use Elixirs and Ethers like basic Potions if you need to.

When the boss casts Dispelga, get those Protectga and Shellga spells back up!