Mystiq.org - forum: Champion / Conqueror of Ulduar -> Dungeons & Raids - T8 -> Bugreport

Note a significant difference in this undying compared to the Naxx undying - there is no stipulation that it must be done within one lockout. So the achievement can be done over multiple weeks of raiding. However the kill must be the first attempt for that week's raid if you wipe and then have a perfect kill it does not count.

edit: Also interesting is that Algalon the Observer is not on the list.

The way it works is such:

*Your raid attempts Freya. You screw up and somehow wipe.
*You recover from the wipe and kill Freya with no deaths. You do NOT gain Conqueror of Ulduar credit for Freya.
*After failing at Freya, you push on to Mimiron and have a perfect one-shot kill of Mimiron with no deaths.
*You gain credit for Mimiron, which will carry over until you finish Conqueror of Ulduar.

All it says now is that you must perform perfect, deathless, one-shot kills of each boss in Ulduar at some point on the raid's lifetime. Nothing more.

Holy crap, finally, how Undying/Immortal should have been in the first place, the goal of doing any boss is NOT to have a single death, the entire instance/achievement could be screwed because 1 dc's/lags is unforgiving. Thankfully, this is now a per boss basis and doesn't include Algalon even, which sounds to be the most painful boss we have come to face.
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