The Doomed TP moves mostly inflict stat down effects, but the damge from Acid Breath and Abyss Blast can hurt. The Disease effect from Undead Mold is long lasting.

This spell can be soloed at level 40. No party is needed for the Phomiuna Aqueducts camp.

Bring Eye Drops for Abyss Blast's Blind effect, and Remedies for Undead Mold's Disease. Be sure to bring level 40 cap weapons and armor. You need to be on, or past CoP Mission 2-3, for access to the best camp. Silent oil, or a sneak spell is needed to get to camp. Have a Ranged weapon to pull. A low damage weapon to feed TP is very helpful.

The best camp for this spell is in the Phomiuna Aqueducts. This is a capped area, so make sure you have level 40 gear and weapons. You need to be on, or past, CoP 2-3 to have access. One Doomed type monster called a Addled Tumor Spawns in the dead end at G-10, it's noted on the map above. Your camp is at F-9 in another dead end, just past the Tumor's tunnel. There are Gloops in the water on the way to camp, so you will need sneak to reach the camp site.

Get to camp and buff up. Then pull the Doomed with your ranged weapon to your safe camp. Be aware that one Gloop lives in the tunnel with the Doomed, and can aggro. Have some patience to make a clean pull, and you should have no problems. Be sure to make your camp far enough back that the wandering Gloop will not aggro while you fight.

The best method for dealing with the Doomed is to enfeeble it, and remove about half it's life quickly, then switch to a low damage weapon to feed TP, and to keep curing yourself to keep your HP up while you wait for it to use the spell. You should be able to get between five and eight TP moves out of each spawn, before it runs out of HP, or you run out of MP to cure yourself.

Respawn here is about 13 minutes. This will give you enough time to run up to the Moogles in the Safehold, and change jobs to remove the disease effect from Undead Mold after a fight, and save some Gil on Remedies.

Doomed have a lot of TP moves, so you may not see Stinking Gas every fight. Also odds are you will not learn it the first few times either, so be ready to spend some time camping the Doomed here. Most Blue Mages seem to learn the spell within five or six spawns.

There are five Doomed type monsters in Garlaige Citadel. Of the lower Fetid Flesh kind, two are behind Banishing Gate #1 at H-7 and H-9 (1st map above) and one more is behind Gate #2 at H-8 (2nd map above). There are two tainted flesh of significantly higher level in the basement at H-8 and H-9 (third map above).

You will need a small party, or skilled soloist job class to kill both types here if you desire the spell when you can use it. The respawn times are long, and there is a lot of aggro at or near all camps. If you choose this option take proper care.

At J-9, in Caedarva Mire, you will find three Jnun type Doomed in the two small lakes. There is sight and sound aggro on the way to this camp, so take care. These are very high level monsters, so you will need a basic EXP party set up to kill them, or a skilled soloist. A Beastmaster can easily kill the Jnun with the local sheep.

Stinking Gas can be learned in a Undead Swarm Besieged. You, a party, or alliance member must get the killing blow on the Expunger for a chance to learn the spell. You do not need to have had engaged the monster yourself to learn the spell.

There are also some other High level Doomed monsters in other places like Arrapago Reef and the Den of Rancor. These options are much harder to reach due to aggro. They are not recommended.