In the Molten Core raid
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When we get to his lair inside the raid the npc of
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Invoke it after a few dialogues, once Ragnaros is invoked
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Before facing us, he kills the npc for Lore's reasons. The problem is that Ragnaros does not kill the npc and we can repeat the Boss infinite times. I leave a reference video of how the mechanics should be.
Molten Core
The Molten Core is located beyond Blackrock Depths in the deepest part of Blackrock Mountain. It is the home of Ragnaros the Firelord--one of the four elemental lieutenants of the Old Gods--and his elemental minions. Molten Core is a 40-man raid instance.
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Majordomo Executus
Majordomo Executus, second in command to Ragnaros, is a powerful flamewaker. He is joined by four Flamewaker Healers and four Flamewaker Elites.
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Ragnaros
Ragnaros the Firelord is an incredibly powerful elemental lord, ruler of all fire elementals. He resides in the Molten Core deep within Blackrock Mountain. Ragnaros has low chance to drop Eye of Sulfuras, the key ingredient to making Sulfuras, Hand of Ragnaros.
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