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Falcorn
#1 - Aug. 25, 2015, 6:15 p.m.
Blizzard Post
Blizzard Hello,

Our developer team is already aware of the issue and is working on a fix! We hope to have it resolved as soon as as possible.

Thanks for reaching out to us here.
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Crithto
Community Manager
#6 - Aug. 25, 2015, 7:13 p.m.
Blizzard Post
The issue with Archimonde should now be resolved. If you're in a raid instance where he is not spawning, you'll want to leave and re-queue.