The achievement for all optional objectives on Hell's Deep unlocked after beating Mira, before I had a chance to take on Rhaskos. This may be related to my earlier reported bug about the Fog of War after Revelation, if a different Red player is being considered Rhaskos.
I'm running windows 7 64 bit
Intel Core i7-3770K @ 3.50GHz (windows detects as 3.90)
24.0 GB RAM
Nvidia GeForce GTX 980 Ti 6GB
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