This is the first named encounter in the zone. Make sure to clear all the trash on the first floor before engaging him. Setup dead center of the room between the two large fire pits, then pet pull him to this spot.
Bubbles of Protection
While fighting Klok once in a while he will put a detrimental on everyone in the raid. The detrimental will be colored either blue or red in your detrimental window. At the same time he will put a large red bubble and large blue bubble nearby. If you have a red detrimental run to the red bubble and stay in there until the detriment wears off. Likewise if you have a blue detrimental then run into the blue bubble and stay there until it wears off.
Once it has worn off make sure to run back to the center area again and continue to fight there.
Gravity Flux
Once in a while he will shoot everyone up into the air. Make sure to use your keyboard to guide yourself in the air so you land exactly back where you were fighting. Watch out for landing in the fire pits (especially when they are active) or you can die from that.
Final 10%
At the end of the fight he will summon up 15+ adds around the room. Provided everyone stayed in the center area most of them should not agro you. There may be the odd one or two but just mez them and burn the name down.