Heroic: The Violet Hold

It's not difficult to get this achievementi. Self-explanatory. You complete the final boss on Heroic VH. As a recap for what other people have said on Cyanigosa's page:

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• Tanks need to make sure she's facing away from the other members of the party.
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• DPS and heals need to stay on the side of her, so she doesn't tail sweep -- never stand behind a dragon (Slabhide in The Stonecore is an exception, don't know if there are others?).
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• DKs shouldn't bother with Army of the Dead.
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• Mana Destruction can be dispelled (magic).
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• She will bring everyone to the center with Arcane Vacuum, just strafe away from her and continue to attack.
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• Don't stand in her Blizzard spell.
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Those are the basics to understanding the last boss. Once defeated, congratulations, you get your achievement! :]

For those who also lack common sense like me and can't find the entrance, it can be found at 66.5 67.8 in Dalaran (The large title "The Violet Hold" on the map didn't ring any bells for me when I went looking for it).



/way Dalaran 66.5 67.8 The Violet Hold Entrance