Team Kaels cleared all the way through General Nazgrim earlier in the week, and on Friday we went back in and killed Malkorok. Our experience with this boss in flex as well as some attempts on Wednesday were very helpful; we managed to get Malkorok down with ease.
The key on this fight is to spread out evenly around his platform so that there will always be a player closely available to soak the three Imploding Energy discs he places on the ground. The discs deal 800K shadow damage to every player that stands in them, put if nobody stands in a disc, it will explode and deal 800K shadow damage to each person in the raid. This high damage is dealt with by another mechanic of the fight: Ancient Miasma, which allows the healers to build up large shields called Ancient Barriers on raid members.
The other important mechanics are Arcing Smash and Breath of Y'Shaarj. For Arcing Smash, Malkorok targets a raid member and does a cone attack that will hit all raid members in the cone for 500K. For the Breath, he causes all areas recently hit by Arcing Smash to explode, hitting anyone in those areas for 1.2M. We had Hyunkel put down markers where the Arcing Smashes occurred so we knew to be out of those areas before the Breath occurred. Once we had the Imploding Energy / Breath of Y'Shaarj dance down, Malkorok was fairly easy. We even had time to do some pulls on the Spoils of Pandaria encounter, and expect to get that next week!