The first instance in Coilfang Reservoir is The Slave Pens. Slave pens have three bulges in total. Here is the fight strategy for the second and third bosses.
Rokmar the Cracker
The second boss in The Slave Pens is Rokmar the Cracker.
This fight is simple. Have the tank grab Rokmar the Cracker and throw him at least 35 yards from the healer. Have the DPS kill him while the party watches all three of his abilities.
The first is Serious Injuries. This is a bleed ability that does 900 damage per pulse and will continue until the target is fully healed or dies. This can only be removed with Stoneform and Divine Shield.
The next ability is Water Spit. This is an area of effect, or AoE, spell that deals 1600-1800 Frost damage to all party members within 40 yards of it.
The last one is Trapping Moss. This is a debuff that slows your casting and attacks by 50%. Be sure to get out of the 30 yard range. If the healer is hit with Ensnaring Moss, the raid will despawn.
Quagmirran
The last boss in The Slave Pens is Quagmirran. He is a basic tank and DPS brawler.
This boss only has two abilities. The first is Acid Geyser, which targets a random player in the raid and spews a cone of acid at them, dealing nature damage. This can be taken away from a player by the tank taunting Quagmirran. He will return to the tank for the duration of the taunt. The second ability is Poison Volley, an AoE or Area of Effect spell. He fires poison beams at everyone who participates in the raid and adds a poison damage over time, or DOT, which can be removed.
Have the tank move him away from the raid so only he gets hit by the Acid Geyser. Healers need to dispel poison DOTs while healing. In the meantime, just have the DPS kill him.
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