Kel ' Thuzad ( original ) Kel ' Thuzad , once a sorcerer of the Kirin Tor of Dalaran , is the chief lieutenant of the powerful Lich King . He ruled over the Eastern Plaguelands from his citadel of Naxxramas . He was voiced by Michael McConnohie . He was the final boss of the original version of Naxxramas and considered by many to be the hardest in the instance due to the stringent execution and DPS requirements . Background . Formerly a sorcerer of Dalaran , Kel ' Thuzad was one of the principal agents of the Lich King , responsible for the spreading of the Plague of undeath across Lordaeron . After being slain by Arthas during the events of the Third War , he was reborn as a lich . He then aided Arthas in summoning Archimonde , a powerful lord of the Burning Legion . However , Kel ' Thuzad ' s true loyalty was to the Lich King , and not the Burning Legion . After the Legion ' s defeat , Kel ' Thuzad supported Arthas in wresting power from the Dreadlords . When Arthas left for Northrend during the events of The Frozen Throne , he left Kel ' Thuzad as his agent to command the Scourge in Lordaeron . Abilities and Strategy . Phase One . Kel ' Thuzad begins the encounter invulnerable , and you need to kill adds which come from the seven corners of the room . This includes the entrance . Phase Two . Kel ' Thuzad becomes active , stage 2 begins 5 minutes and 10 seconds after you engage him . Kel ' Thuzad has approximately 3 , 150 , 000 hit points . He is immune to taunt . Frost bolt single 2 second cast . Inflicts 9 , 000 to 11 , 000 Frost damage to primary aggro target and reduces its movement speed for 4 sec , must be interrupted as it will one shot or nearly one shot the main tank . Frost bolt is cast at random intervals and is often chain casted , having multiple rogues and warriors meleeing Kel ' Thuzad at all times is ideal . This spell is not resistable . Frost bolt multiple Inflicts 2 , 750 to 3 , 500 Frost damage and reduces the targets ' movement speed for 4 sec . Hits everyone in the room and cannot be interrupted - it is instant cast . Used every 15 secs . Fully resistible . Chains of Kel ' Thuzad Kel ' Thuzad can mind control 5 people at once . Size increased by 200 % . Charmed . Damage increased by 200 % . Healing increased by 500 % . They will buff and heal Kel ' Thuzad . Can be CC ' d by any ability that would normally work on humanoids . This ability will wipe all threat . This ability will always target the player with the highest aggro ( I . E . the main tank ) requiring a tank switch . This spell has a cooldown of 60 seconds . Mana Detonation A debuff randomly applied to a mana using player . The player will explode after 4 seconds , dealing Arcane damage based on maximum mana to all players within 10 yards ( not to himself ) . This will burn half of their current mana pool . This spell has a 20 second cooldown . Shadow Fissure Summons a very noticeable red fissure around the targeted player which does 62500 - 137500 shadow damage after 3 seconds as Void Blast . Easily avoidable by running out of the fissure . This spell has a 10 second cooldown . Frost Blast Places an Ice Block effect on the targeted player , and all players within 10 yards , rendering them unable to perform any action . This effect will continue to chain to anyone within 10 yards of anyone affected as with C ' thun ' s Eye Beam . It will deal 130 % of their maximum HP in damage over 5 seconds . If those affected are not healed within 4 seconds they will die . This spell has a 30 second cooldown . Phase Three . At 40 % health , Phase Three will begin as Kel ' Thuzad calls for aid and the Lich King sends five Nerubian Crypt Lords known as the Guardians of Icecrown to attack the raid . 40 - man Level 60 Strategy . You will need 6 - 7 tanks and 10 - 13 healers for this encounter . Frost resist gear is not generally advisable since you ' ll need all the DPS and mana regen you can get . The main tank also cannot resist Kel ' Thuzad ' s frostbolt anyway . Phase One . Gather in the middle of the room , make sure all pets are on passive . Ranged need to all be on the Soldiers and Soul Weavers . Healers can help DPS Soldiers . Melee are on the Abominations . It ' s incredibly important that all raid members are aware of the Soldiers coming at the raid . Although they only have 5 , 000 HP one touching the raid will take everyone down to 40 % HP or so . Two hitting the raid will be a wipe . Have someone call out the Soul Weavers as soon as they acquire a target . They have a lot of HP and if they reach the raid there will be deaths . Abominations need to be killed as fast as possible without pulling aggro . They hit for about 4 , 000 on a tank and stack mortal wound . More importantly they spawn progressively faster as the phase goes on and you don ' t want any up when Kel ' Thuzad attacks . You will definitely still have some Soul Weavers up as Kel ' Thuzad spawns so ranged need to finish them off . Phase Two . This phase needs to end as fast as possible so your healers have mana for phase three . A tank should pick up Kel ' Thuzad as he spawns and drag him to the middle of the room . Make absolutely sure your interrupters are on the ball here . Kel ' Thuzad is capable of bursting for 14 , 000 unresistable damage on a tank with a frostbolt into volley if you do not interrupt him which will kill any tank without shield wall up . Like most bosses Kel ' Thuzad is immune to taunt . He has 3 , 150 , 000 hit points . Positioning will be the critical part of this phase . The melee need to establish a diamond around Kel ' Thuzad ' s hit box with 8 yards between them to make sure less than 6 melee are hit at a time by Frost Blast . When Shadow Fissure hits a melee clump you ' ll need to move away from Kel ' Thuzad then back in . If the melee are in groups of five Prayer of Healing can save them , as well as Chain Heal if you are a Horde raid . You ' ll need mulitple healers hitting all the melee however as Frost Blast hits for 130 % of their HP . The rest of the raid will need to be in a circle around Kel ' Thuzad with 8 yards between them . Mana detonation will cause a lot of deaths unless you stay spread out , and remember that Frost Blast can chain through the entire raid if you do not keep spaced . Although it is tempting to drop melee for this encounter too many ranged will result in running out of room to fit 40 spread out people in . Healers will need to be ready for both burst healing on Frost Blast every ~ 30 seconds and Frostbolt Volley which hits for about 60 % of a raid member ' s HP every 15 seconds . Kel ' Thuzad melees for about 3 , 000 on a tank . Kel ' Thuzad ' s most dangerous ability is Chains of Kel ' Thuzad . This will mind control your main tank and four others ( possibly other tanks ) , wiping threat . Melee need to be especially careful to stop DPS when this comes as Kel ' Thuzad is not tauntable . Whichever tanks are not mind controlled need to to immediately fight for threat on Kel ' Thuzad while interrupts need to continue to avoid tank deaths . Anyone with a humanoid CC ability will need to use it , especially Mages , to control the mind controlled players who hit VERY hard and heal Kel ' Thuzad for 500 % healing . Mages should keep detect magic on Kel ' Thuzad so the raid is aware of any buffs he may gain . Kel ' Thuzad uses this ability randomly , as often as every minute or sometimes every two minutes . ALL of his other abilities carry on while this is in play so don ' t lose focus . Phase Three . At 40 % HP Kel ' Thuzad will call for aid and the Lich King will send five Guardians of Icecrown at the raid . Three priests should be assigned to shackling these ( no more or Kel ' Thuzad will dispel your shackles ) . They obviously will need to run through other raid members so make sure people stay aware and move away to stay spread out . Two tanks need to be tanking Guardians that are free and they will be taking a lot of damage . Guardians gain 15 % damage every time they switch targets or a player dies so try very hard to keep them under control or your tanks will explode . Guardians are tauntable . This means you will have less tanks on Kel ' Thuzad during a chains and sometimes Guardian tanks will have to try to pick up Kel ' Thuzad , which is a good time for Shield Wall . Kel ' Thuzad ' s other abilities continue at the same rate so this phase can quickly become very frantic , especially if your Priests die . Try not to let DPS get overly excited and pull aggro during or after Chains of Kel ' Thuzad as deaths will quickly escalate the encounter out of control . Raid buffs such as an Onyxia head turnin and full flasks are VERY helpful for the last 40 % . This is the most difficult encounter in WoW 1 . 0 . Good luck ! Quotes . " See Kel ' Thuzad for quotes from his WCIII script . " Dialogue with the Lich King upon death of Sapphiron : Death of Mr . Bigglesworth : Taunts when the final bosses of the first four wings are killed : Phase One : Phase Two : Phase Three : Mana Detonation : Dispelling : Chains of Kel ' Thuzad : Frost Blast : Killing a player : Death : Videos . < br > Kel ' Thuzad at 60 . < br > < br > Kel ' Thuzad ' s original voicework .