THIS METHOD NO LONGER WORKS AS OF PATCH 3.0.8
This fight can be very hard if you try it the way others tell you to do it. My guild found a secret to this fight that makes it super easy. See the details below the video.
Recommend watching this in HD by clicking the "HD" button and fullscreen by clicking the "Fullscreen" button in the video controls.
Heigan the Unclean How To
The key to this fight is simply to run from one exact point on the rooms floor to the far corner of the platform. Heigan will cast disease on raid members that should be cleansed immediatly. Rinse and repeat. Its simple as that.
When Heigan is loose the tank should tank him at the corner of the platform as seen on the video. The tank and melee DPS should stand on the very edge of the platform with Heigan standing on the rooms floor. The ranged DPS should stand on the far corner of the platform as seen in the video.
When Heigan teleports the entire raid must run to the exact point that I show in the video and stack up. Its easy to spot. It looks like three green lines in the floor point to it.
You can do this with no deaths and get the achievement. I died in the video cause I got the disease and died before I was cleansed. My very first trip here, everyone but a tank, a dps, and a healer died. They proceeded to three man it until something went wrong and they wiped.
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