Yes, Abaddon wore Terminator armor at that point-- and he is in that picture (it's the link... couldn't get the [img] tag to display correctly.) The Marine is just a random trooper.
I was kicking around what Codex I'd use for a Pre-Heresy army, and I'm kind of leaning towards Space Wolves. More free-form than Codex: Space Marines, but most of the same general squad types. And Grey Hunters are closer to Chaos Space Marines (as far as how they play) than Space Marines are to Chaos Space Marines, since they have a bolter, bolt pistol, and close combat weapon. I think I want to downplay the Chaos element of the army... it'll be there, but it'll be subtle. The Black Legion has ten thousand years to become what they are at the end of the 41st millenium. The artwork shows some chaos icons here and there... mostly more and more arrows added to the Eye of Horus until it's the eight pointed star when the Legion fights on Terra.
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