Stepping Through the Darkness

This quest requires you to obtain [item=174782] from a "Corrupted" zone in a Horrific Vision. You only need to clear one of the two available Corrupted zones to get the item. (If you clear both, each chest at the end will reward the quest item but you can only collect one.) You do not need to kill Thrall or Alleria.

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Each Horrific Vision has three tiers of zones. Higher tiers will drain your sanity at a higher rate and, in general, will be prove to be more challenging than the previous tier(s).

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• "Tainted" (Tier 1)
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• "Corrupted" (Tier 2)
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• "Lost" (Tier 3)
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Vision of Orgrimmar

Tier 1 (Tainted)

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• Grommash Hold: Defeat Thrall to end the Vision
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Tier 2: (Corrupted)

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• Valley of Spirits: Help Zekhan save Orgrimmar's shamans.
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• The Drag: Evacuate Garona and the civilians.
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Tier 3: (Lost)

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• Valley of Wisdom: Help Geya'rah get revenge.
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• Valley of Honor: Defeat Rexxar and his creatures.
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Vision of Stormwind

Tier 1: (Tainted)

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• Stormwind Cathedral: Defeat Alleria to end the Vision.
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Tier 2: (Corrupted)

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• Trade District: Free the captives.
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• Dwarven District: Aid Kelsey and play with explosives.
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Tier 3: (Lost)

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• Mage Quarter: Stop Magister Umbric's assault.
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• Old Town: Assist Vanessa with some Defias Company downsizing.
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Don't do what I did and waste a vessel by killing the boss expecting to get the quest item. You need to defeat a secondary wing of the map. This quest is different than the first 5 ranks. Would be nice if Blizzard made that clearer.

Just complete a secondary wing. Get it at the end when opening the chests.