The Aurum Vale is full of yellow pools and gas geysers. While standing in the pools, you will suffer from Goldbite, a powerful DoT. Meanwhile, the gas geysers do not do damage and instead trigger a minor knockback. This can either push you into a yellow pool or, if you are speed running, into a trash pull.
Clearing this dungeon will reward 40 Allagan Tomestones of Philosophy.
When walking into the boss' chamber, you will notice Morbol Fruit along the walls. Each player should stand near one, as you will need to consume it during the fight. This fight is primarly a healer fight, with everyone else doing their best to avoid Gold Dust.
We choose to eat the Morbol Fruit right after the second stack of Gold Lung lands. The Morbol Fruit will always have respawned by this point, and it prevents anyone from being stuck at two stacks for a prolonged period of time with no fruit. The tank will have to time using the the fruit between Locksmith's melee swings.
This boss drops 4 Allagan Tomestones of Philosophy.
Coincounter only has a few abilities, but each one can be deadly. He has two swings that the tank needs to avoid. If he only uses one hand, he will use 100-Tonze Swipe, a frontal cleave, so run through the boss to avoid it. However, if he grips the mace with both hands, either stun him or run away, as he will do a 100-Tonze Swing, dealing enough damage to kill even the tank. Neither version of this ability has a ground indicator.
Meanwhile, the ranged will frequently be targeted with Glower. Coincounter will select a random player and will shoot a beam at them. Everyone should be positioned so that the beam will only hit a single player. This, for example, is poor positioning. He will also cast Eye of the Beholder, which can easily kill you if not dodged. As soon as you see the emote "The Coincounter takes a moment to reconsider..." run into melee range of the boss. You should try to stun this, if possible. Once Eye of the Beholder goes off, it's important to move away quickly, as even 10-Tonze Swipe is extremely painful for a DPS or Healer.
This boss drops 8 Allagan Tomestones of Philosophy.
Starting off, Miser's Mistress should be faced away from the group, both to avoid the cleaving attack Vine Probe and to avoid Bad Breath hitting the group. The tank should also be dodging Bad Breath, as that is too many debuffs to remove quickly.
Like Locksmith, this boss has a debuff, Burrs, which will need to be purged by consuming a morbol fruit. While there are more of them this time, they do not respawn nearly as often. We removed the Burrs stack every 3rd stack. This caused the Burr Burrow applying the 3rd stack to deal ~1100 damage, which was managable.
At 50% and 25%, Miser's Mistress will run to one part of the room and spawn five Morbol Fruit (The eggs) around it. These must be killed extremely quickly. As a WHM, I tossed in a Holy with Cleric Stance up to help out. If any hatch, the Morbol Seedlings will apply one stack of Burrs every melee swing and will cast Germinate to further stack it up. If any Seedlings do survive, kill them quickly.
This boss drops 28 Allagan Tomestones of Philosophy.