(Mojarn Piett @ Apr. 04 2007,08:48)
QUOTE
Not much, I'm afraid. The Nurgle Legion (Death's Heads) was the best detailed of them all.
IIRC the Khornate Legion was named Flaming Skulls but I don't remember seeing any background info for it.
Flaming Skulls, Stormlords and Death's Heads are not explicitly described as belonging to any particular power. Their attributions to Tzeentch, Slaanesh, and Nurgle, respectively, comes from the game pieces in the Horus Heresy game. Those legions' pieces were colored to match the powers.
The background text that Ratty quoted pretty much states, or at least very strongly implies, that the Flaming Skulls and Stormlords are Khornate - "towering black war engines of the Khornate host" - so there is a conflict. I tend to go with text over a game piece, so I listed them as "Probably Khorne, possibly X" on the reference sheet.
That also throws the question of the nature of the game piece colors into serious doubt. If those legions are pretty clearly not directly associated with the game piece color allegiance, would it hold for the others? It's still evidence, but pretty weak at that point.
No reference is ever made to the Death's Heads being Nurgle anywhere beyond the color of the game piece. There is another potential Nurgle connection in that they scoured Istvaan III which, iirc, was after it was virus bombed but it's not specific in reference to Nurgle. They are featured as the legion that breached the Imperial Palace and are as a result hated by the Fire Wasps who are the Palace Guard. They are not represnted as being Nurglesque in either the Horus Heresy text, nor in any of the Fire Wasp background material, which would seem to be a notable omission.
Given the dubious authority of the game piece and the lack of any direct reference, I've counted them as "probably undivided, possibly Nurgle" on the sheet.
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The whole pursuit of titan legion background is rather like trying to fit together various versions of medieval texts into an "authoritative" version.