Klaaktuus on Normal Mode is a rather simple fight. Survive the successive AOE's just like on the normal mode encounter of Oxydaxius. Klaaktuus does have some similarities to Oxydaxius in that there are three adds that will spawn every 30-45 seconds or so.
However these adds are immune to all AOE attacks. You must kill each add individually. This can be rather hard because of the lag that usually accompanies this encounter. Bring EXTRA dps if you can. The AOE's do not hit for that much at all.
The other part of this fight controls the "Challenge Version". If you want to maintain the normal mode of this encounter then all you need to do is not kill the named erudite that accompanies Klaaktuus. Keep him alive, mezzed preferably and when you get Klaaktuus to 20% the encounter will end. If you kill this NPC you will trigger the Challenge mode.
Keep all massive single target dps assisting one person to kill the adds and you should drop Klaaktuus rather quickly.
Challenge mode is started by killing ALL of the adds that start with this encounter.
Klaaktuus has a mem-wipe that occurs every 30-40 seconds so you will need to tanks on him at all times. After he mem wipes he likes to do an AOE roughly 10 seconds later so get that mob back.
He also has a fear that will hit randomly in your raid. Be sure that you have walk and crouch on so that you do not go running off the side or anything like that.
The Imps are the same in this fight except for one addition. There will be a new single add called a "Banshee" that needs to be killed first and foremost. You still need to kill the IMPS quickly but that Banshee needs to die super quick as well.
This fight is still yet another DPS check and with the contested lag that you will encounter it will be a bit tricky. If the fight was not lagged at all this fight wouldnt be nearly as difficult.
There is also a curse that needs to be cured before it expires but if you have atleast 2 healers per group you shouldn't have much of a problem.
3 Scarlings that need to be pulled soon as they pop or they will heal the named, can not hit them with AEs so have to single target each down. Banshee that will spawn and likes to AE stun, fear the raid, must also be dpsed down. Single target curse on MT about every min that will fear the tank. Memwipe on MT about every min as well.