Hydromancer Thespia

Hydromancer Thespia is the first boss of The Steamvault in Coilfang Reservoir.

Abilities
Heroic: Thespia can cast 2 clouds at a time. Heroic: Thespia can stun 2 people at once.
 * Lightning Cloud: Instant-cast AoE DOT. Causes 1600 to 2000 damage when it appears, and adds 1500 to 2500 Nature damage/sec, in a 10 yard radius.  Get out of this as quickly as possible.
 * Enveloping Wind: Dispellable Magic debuff that stuns a random player for 5 seconds. If stunned in the cloud, it will no doubt be deadly.
 * Lung Burst: Dispellable Magic debuff for 500 per tick (675 in Heroic).
 * 2 Coilfang Water Elementals: Can be Banished. They cast Water Bolt Volley (900 Frost damage to everyone in LOS+range; 1900 in Heroic).  These should ether be killed or banished before Thespia is touched.

Strategy
Hydromancer Thespia is accompanied by two water elemental adds: Coilfang Water Elemental, each with around 16,000 HP. The elementals can be banished. They have a volley spell that deals approximately 900 frost damage. The adds should be killed before DPS begins on Thespia. They can be brought outside of the room where Thespia resides to avoid her attacks. As of 2.1.0, the elementals will now despawn once Thespia herself dies.

Thespia will occasionally cast a Lightning Cloud which deals a large amount of nature damage per second when underneath the cloud. Typically if you're under the cloud for more than 2 or 3 seconds, you will die. Run from the cloud to avoid taking damage. The cloud will not always be cast on the tank (regardless of aggro), so healers and ranged DPS must be ready to move if the cloud is cast above them. She tends to cast the cloud on groups of people, so keep everyone spread out as best as you can. If you have a lot of melee, expect the tank to have to kite her around the room a lot. Nature resistance gear and potions can help mitigate any mistakes, but by and large you should seek to avoid getting hit at all.

Thespia's other ability puts the debuff Enveloping Winds on a player. This prevents the player from being able to move, which can be especially deadly when caught beneath a Lightning Cloud. (As a bear tank, I've only had this happen to me once in the time it took me to get exalted with Cenarion Expedition. Needless to say, we wiped.)

If your tank or healer goes down and you want to save a total wipe, you can drop down on the small ledge to the right of the top of the ramp leading to her room and run around out of LOS. She will stand there a little bit and then reset, saving you a walk back or running all the way to the instance door with her chasing you.

Heroic
In Heroic mode, the elemental's waterbolt volley does approximately 1900 damage. DPS must be quick to kill the adds. The elementals can be stunned, significantly reducing the amount of damage taken before they are killed. You can also counterspell, bash, etc. their volleys. Also, Thespia casts 2 clouds at once.

A warlock, although not required, makes this boss fight trivial (especially in Heroic, when the adds melee cloth for 1.5-2k). Repeatedly banish one add and chain-fear the other while the rest of the party burns her down.

Alternatively, a sufficiently group may choose to kill the two adds first, especially if a reliable crowd controller is not available for the fight. The tank of the group can either hold all three mobs (which will put a severe strain on healing) while the adds are burned down, or the tank can hold one add and the Hydromancer while the group either kites and kills the second add, or has a hybrid melee class tank and kill the second add.

Another strategy uses a hunter to kite Thespia. Have the hunter park his pet as far away as possible - for example in the water on the far wall of the cavern - misdirect Thespia to the pet, and after Thespia kills the pet, the hunter kites Thespia to the entrance. This gives the group more than enough time to burn down the water elementals, and then fight Thespia by herself. Note: Thespia does not always seem to go for the hunter after killing the pet; however, if the pet is stationed such that Thespia takes a detour to get to the ramp, just the pet can provide enough time to down at least one of the water elementals. The warrior will need to pick up Thespia on the way back while the rest of the party finishes off the second water elemental if necessary.

The Vial of Underworld Loam for the quest will not drop in heroic mode.

Quotes
Aggro: Lightning Cloud: Killing a player: Summon: Death:
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