Nefarian is the eighth and final boss of Blackwing Lair. He was particularly notable back in the day for his class calls, so much so that when Blizzard added death knights to the game, they went back and added a class call to Nefarian as a tribute.

Every 25-35 seconds, he will "call out" a class, afflicting every player of that class with a specific debuff.

• Druids are forced into Cat Form for 30 seconds by Involuntary Transformation.
• Death Knights will Death Grip players into him.
• Hunters have their equipped ranged weapons instantly broken.
• Mages are transformed into a giraffe, cow, or worm by Wild Polymorph.
• Priests are afflicted with Corrupted Healing, causing the targets of any direct heals they cast to be debuffed by Corrupted Healing, dealing 44 to 56 damage every 1 sec, stacking up to 50 times.
• Paladins receive Siphon Blessing, forcing them to continuously cast Blessing of Protection on Nefarian.
• Rogues are teleported in front of Nefarian and immobilized, leaving them open to his Cleave and breath attacks.
• Shamans will be under the effect of Corrupted Totems, summoning powerful versions of the Shaman's various totems that will buff Nefarian and damage the raid.
• Warriors will Berserk, forcing them into a modified (Spell #2458), increasing damage taken.
• Warlocks will be forced to Summon Infernals, summoning two Corrupted Infernals per warlock to start attacking the raid.