I was aware of that passage under Doombreed
, however it seems contradictory to other parts in the codex and even other modern lore. I'd also just like to throw in the timeless issue that the warp is timeless, therefore applying the word "young"
to Khorne is a paradox.
There is also other pieces of lore which implies the chaos gods are much older, Codex: Necrons
for example which states 60,000,000 years ago the warp was thrown into disarray as a result of the War in Heaven, implying in it's wording that this is when chaos began to rise.
Ultimately though I refuse to believe that the first three chaos gods manifested during the rise of mankind (unless it is a pure coincidence). Simply because this implies mankind played a significant role in their manifestation. You can't honestly say that humanity's petty conflicts across a single world brought about the rise of Khorne, when for 60,000,000 years across the entire galaxy (if not universe) inter-planetary through to plausable inter-galactic warfare was being waged. The War in Heaven itself is noted as a conflict the likes of which the universe has never seen again, this conflict in itself would have contributed significantly to the rise of Khorne rather than semi-intelligent monkeys bashing each other with sticks.
This can in turn be cross referenced with the rise of Slaanesh. A galaxy spanning empire with trillions of subjects who are one of the most (if not the most) psychically attuned species in the galaxy took thousands of years (possibly up to a million according to Codex: Eldar
) to give rise to Slaanesh. I refuse to believe mankind gave rise to three chaos gods in the space of a couple thousand years (and that's being generous) even when civilisation had barely started on Terra and wars in general had few casualties and minor bloodshed compared to other conflicts raging in the universe.