Oh yeah... I remember that mission quite well. 100% Paragon Protectors. It's like a bad dream that you cannot wake up from. (Athough it was still killer farming even before IO's =P)
I think the devs were going for a "Black Hole" movie kinda look. The blank faceless helms... really the effect is kind of creepy when you think on the entire arc. Those are dead heroes brought back to life through cloning and conditioning.