Minutes to Midnight

the majority of the raid has to port out of the twilight realm in order to avoid taking damage from [spell=103327]. in order to get this achievement, you have to plan a rotation order for only keeping people in the twilight realm once. if too few people stay, the aspect NPCs die.

on 10 normal, you must have one player stay in the twilight realm.
on 25 normal, you must have three players stay in the twilight realm.
on 10 heroic, you must have two players stay in the twilight realm.
on 25 heroic, you must have five players stay in the twilight realm.

this achievement is a dps race in that the faster you kill the boss, the fewer raid members/cooldowns you will have to cycle through.

Tanks can use their standard cooldowns that they use to survive [spell=109415], however you will need others using cooldowns for up to 5 more Hours of Twilight. Here's a list of what non-tanks can use to survive the damage:

• Death Knights using Anti-Magic Shell and [spell=48792] (or [spell=51052] for Unholy);
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• Feral Druids using [spell=61336] and Barkskin;
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• Paladins using [spell=498] (glyphed with [item=41096]) or Divine Shield;
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• Warriors using [spell=871] ([spell=63329] if needed);
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• Shadow Priests using [spell=47585];
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• Mages using [spell=45438] and Fire Mages, thanks to [spell=86949];
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• Hunters using [spell=19263];
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• Rogues using Feint or Cloak of Shadows;
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• Holy Priests using [spell=47788] on any player.
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Almost certainly a reference to the Doomsday Clock (which represents the threat of global disaster), since the goal of Ultraxion is to bring about the end of the world, rather than a reference to Iron Maiden's album "2 Minutes to Midnight" or Linkin Park's album "Minutes to Midnight".