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human
[40k]Who is still around from the time of the Emperor and the Horus Heresy?

I've been doing a bit of reading and I came across this supreme badass named Bjorn the Fell-Handed who still remains living by means of a Venerable Mars Pattern Mark V Dreadnought. While he spends most of his time in stasis are there any others that still are in service to the Imperium of Man or the Ruinous Powers? I know that some of the traitor primarchs became daemon-princes and are still mucking about, but do they do anything? Chaos forces always seem lead by one of their officers rounding up a war party.
gpt
A lot of Chaos Space Marines are from the days of the Horus Heresy that fled to the Eye of Terror.

Thanks to the fact the Eye is basically on the border of the Warp, time is funky around there. Some Chaos Space Marines are 10.000 years old (Like Abaddon the Warmaster) and others just feel they were in the Siege of Terra like, 8 years ago.

Most daemon-princes don't do much outside the warp because it's really bloody expensive (in blood) to summon them. Angron got out once, it took a massive crusade to fix the damage he caused and Magnus was sighted on Fenris not so long ago, wreaking the Space Wolves stuff (Battle of the Fang).

But with the Loyalist, we only know of Bjorn the Fell-Handed.

Some Primarchs are still hinted to be alive, such as Leman and Vulkan. Leman on the state that there is some hint that the thirteen company of the Space Wolves who followed Leman to the Eye of Terror is still around. Vulcan on the fact he can't die.