Have your party at least at level 50. It is a good idea to save in the land of the Garif; it is the last save spot you will see before this battle. Go to the farthest area in the Ozmone Plain, then go down into the underground cavern called the Zertnan Caverns. Follow the cave though the status-inflicting horses until you reach the third room. You will know you are there when your mini-map gets fuzzy and there is a sandstorm to your right. If you have any damage or you need to get back MP, heal them now for an advantage in the fight. Remember, there is no save crystal before the fight. You should have at least three long range weapons equipped. He is a flying Boss. Also, give the people with long range weapons the best Ice spell possible. He is a Thunder type, and is weak to Ice. One of the most annoying things in this fight is the corpse that appears. The best strategy is to have two people deal with the corpses and one person hit the Esper. You can make the "zombie attacks" attack the zombies immediately if you make their Attack Gambit into Foe, Undead/Attack or Foe, Undead/Curaga to make it so that they attack them. The person who attacks Adrammelech must have a long range weapon. It is best if you control the one attacking the Esper. He sometimes uses his Thundaja attack. It can do a lot of damage and inflict Stop on some of your characters. Just use a Chronos Tear or a Remedy with Remedy Lore 3 to get rid of it. If your first team dies it may be a good idea to use some Quickenings to turn the table. Keep everyone above 60% HP and keep hacking away until the the Esper falls and becomes yours.

This Esper is located at Athroza Quicksands in Zertinan Caverns. The place where you fight him has many other monsters that join him. Do not attempt to fight him until you can routinely kill a numerous amount of level 40 monsters at the same time. Keep in mind he is not summoning them. If you can keep from pushing the battle to areas you have not yet walked on you should be able to stop them from springing up from the ground. One monster spawns for about every one or two square feet in relation to your character.

Before looking for him, you should have Vaan, Penelo, Ashe, Basch, Baltheir, and Fran with you. They should know all of their Quickenings. Once you get to him you should have everyone at level 18 or higher. Have one person use Cura or Curaga Magick in your party and on the zombie things that come out of the ground, at least 5 Ethers, and in Config set the Battle mode on "Wait". Start by
having only one person in your party (preferably your weakest). Then, immediately have them use their Quickening. Then just after
bring out another person (the second weakest in the group) and keep out the person you used before, use their quickening immediately.
Then bring out another person and use their quickening. Next put your weakest member into your reserve and bring out another person
to use their Quickening. Repeat this until everyone's MP is zero. You should have done six Quickenings. By this time, if you did at least a seven-combo Quickening each time he should have about 5% of his health remaining. Restore the person using Healing Magick's MP and put your weakest person out until Adramelech uses the big thunder attack. Then, switch out your strongest people to attack him and finish him off.