Fathom - Lord Karathress Fathom - Lord Karathress can be found in Serpentshrine Cavern and is usually killed as the fourth boss . The fight involves several adds ( similar to High King Maulgar ) , and is a battle for survival which is made much easier by high DPS . After killing Karathress , becomes accessible . Raid composition . The group with the Tidalvess ( Shaman ) tank should contain a shaman , who keeps Grounding Totem up at all times , to negate Tidalvess ' Frost Shock . Due to the mechanics of Fathom - Lord ' s Cataclysmic Bolt , paladin tanks are not advisable for this fight . Damage caused by this ability to a tank with ~ 18 - 20k health is very difficult to heal through and can easily cause a wipe for entire raid . Kill Order . Since Blessing of the Tides is a rather evil buff for the boss , it ' s reasonable to kill the adds first . The priest is the easiest add to control and should be killed last . Whether the shaman or hunter has to be killed first is a matter of choice . The hunter drains mana , the shaman deals the most damage - if the two main tanks both have good gear , it may be better to kill the hunter first . The following kill order minimizes the damage taken by the raid : Every time an add dies , Karathress gains a new ability ( similar to the Anubisath Mobs in the Temple of Ahn ' Qiraj ) : Positioning . First the entire room and the patrol in the next passageway must be cleared . Tanks list : The shaman and the priest both have a 45 yard AoE spell . After the shaman ' s dead , Karathress gains that ability from the shaman . Thus the best setup would be to have the boss , the shaman and the priest all 45 yards apart from everybody else . Unfortunately such a setup has not been found so far , so usually the priest add gets a small group in one corner , the boss is tanked near his initial position , while the hunter and the shaman are killed away from the other mobs . On the pull , Misdirection is best used on the Shaman add ( to prevent him from taking out the Karathress tank with a damage burst ) , on all other mobs it ' s optional . Spitfire Totem . During the whole fight , the spitfire totem is a major source of raid damage . While adds are still up , it ' s absolutely necessary to bring it down ASAP when it spawns . All ranged damage dealers should have a macro to quickly target it i . e . / target Spitfire Totem . When only Karathress remains , it ' s possible to ignore the totem and simply heal through the damage . Caribdis Group . One warrior off - tank , a rogue and a shaman healer is the smallest group able to control Caribdis . Adding a warlock , a mage or an additional healer makes the job easier , but also slows down the killing of the other adds and / or makes raid survival more difficult . The purpose of the priest add group is to interrupt all her heals . The rogue should use Mind - numbing Poison . When the two melee classes are frozen , the shaman healer must pay extra attention to be ready and use rank 1 Earth Shock when she starts a heal . Adding more melee damage dealers to this group is pointless , it only increases the load on the healer . If heals keep getting through , a warlock may keep Curse of Tongues active on her , and if the warrior or rogue die frequently it helps to have a second healer paying attention to this group . The healer ' s job is easier if this group can stay 45 yards away from all other mobs , so that the random damage spells from the other mobs don ' t interfere . Quotes . Aggro : Killing a player : Killing Caribdis , Sharkkis , or Tidalvess : Misc : Upon Gaining Blessing of the Tides : Death :