What khorne was in very old fluff.
This sums up my thoughts
from 1d4 chan
Khorne and His Worship
Khorne is the easiest god ever to worship. Where other more pussified
(Oh go to hell Imperials, you know it's true) gods may demand you to memorize overly long prayers and hymns, or to build huge houses of worship and other such gay bullshit, Khorne is venerated with one thing and one thing only. The time honoured tradition of hack'n'slash.
Khorne is worshipped on the battle field. His hymns are the sound of steel on steel, his prayers are the blows of hammer and axe and the bellowing of 'Blood for the Blood God! Skulls for the Skull throne!".
In essence, you worship Khorne by being a good warrior. And as a warrior, you'll find your interests and his tend to generally align; he wants death but isn't picky on who, and you want to live to fight another day. Thus, the mere act of preserving your life will earn the pleasure of the god of death. Ironic, no?
However, Khorne is one of those honourable war-gods. So don't think that beating your enemies by anything other than sheer strength, skill and aggression will make him happy. And for the love of Sigmar/Empra, don't try to cheat by picking fights with the weak or helpless or by giving him baby skulls.
Khorne expects a form of savage, Viking-esque dignity from his followers and for them to be generally badass, this means you have to fight worthy opponents and those generally able to at least hold up a sword. After the manly enemies are out of the way; gorge yourself on the blood of women and children all you want. Most of the writers forget this, thinking that Khorne really gives no fucks about what you kill, and it makes Khorne snarl in anger. Though he continues to send his flesh-hounds to hunt down those who flee and abandon their brothers on the battlefield, be they Chaos or non-Chaos.
Aside from that, Khorne has no commandments whatsoever. But deviating from the aforementioned in the slightest is begging for the Flesh-Hounds to tear your ass apart.
Such as it is, it would be incorrect to think Khorne doesn't have priests dedicated to him. Though, being a warrior god, these priests tend to be warriors themselves and are often marked by their god. In essence, the only difference between them and a Chaos marauder/Space Marine is several pounds of armour. In Warhammer Fantasy, these priests are called 'Bloodfathers', and in lieu of magic that is gifted to their priests by other gods, Khorne just gives HOLYSHITAWESOME
fighting skills and visions of bloodshed.
Khorne is also venerated by working brass into your armour and weapons and donning fashionable high collars. Occasionally, a warrior so pleases Khorne that he gifts him with specially made ones that in addition to looking fabulous can also grant total fucking immunity to magic.
Anyway, Khorne is worshiped by warriors, generals and basically anyone who likes battle. His chosen Space Marines legion is of course the World Eaters, in Warhammer Fantasy, the Norscans tend to venerate him with the greatest piety, especially the Aesling tribe, who are Khorne's most devoted servants in Fantasy.
As posted by an Anon some time ago, he perfectly summed up what Khorne's opinion on magic is:
Okay, here's what the "FUCK WIZARDS" thing means.
Note that the hate of psykers/wizards/etc is pretty much the exact same and works by the same logic for both Khornates and the SoB/Black Templar/etc. Its a Conanesque kind of swords and sorcery thing. Khornates hate wizards for trivializing encounters with a single spell and overshadowing fighters. They hate turning what should be a military endeavor into a weird wizard show where people turn into frogs. They hate Slaaneshi for the same reason, they take what should be a wholesome murder fest and make it into something creepy and weird, what with them "discomporting themselves with the dead" and all that. In Realms of Chaos, its entirely possible for a librarian or wizard to go to Khorne. They just refrain from using their powers, and only use their psi/magic (in combat) to resist spells from that point onward.
They are okay with laser beams. They are okay with sniper rifles. They are okay with flaming swords. They are okay with running people over with tanks. They are okay with chemical gas. They are okay with exterminatus. They are okay with holocausts. They are okay with blitzkriegs. They are okay with stabbing people in the back. They are okay with honorable duels at dawn.
They are not okay with turning people to frogs, mind controlling people, raining glitterdust from the skies to blind everyone, raising armies of zombies to do the killing for you, and so forth. They are not okay with someone pointing their finger and you dropping dead. They are okay with rituals to summon demons. They are okay with navigating the warp without crashing into suns. They are okay with sending astropathic messages.
They are okay with chaining wizards up and forcing them to eternally forge magic items on pain of death.
You may consider it hypocritical that Khornates are okay with blatantly unfair TECHNOLOGICAL murder, but not okay with blatantly unfair MIND/MAGICAL murder the point is, or at least one interpretation, is that wizards/psykers fucking cheat. They do.
They steal the power of the Warp for their own ends. As long as they stay in line, and do nothing but permit the warrior to enact his craft, fine, let them live, albeit in terror, enslaved by chains of brass until the day they are no longer useful, at which point their skulls can join Khorne's throne.
But stealing the Gods' own fire and using it to do what mortals should do through their own skill and strength is unacceptable. Remember that technology is completely valid to Khorne. Stealth is completely valid to Khorne.
Skill is completely valid to Khorne. Cleverness is completely valid to Khorne. The nuclear bomb and other innovations that come after it could be seen to be unfair. But it is a mortal invention. Mortals should give honor to Khorne by murdering each other through the sweat of their brow.
The scientist who devises new ways to kill is a saint. His work can be put to any other use -- enriching human life, ending hunger, fighting diseases, answering great questions. But the scientist who devises new bombs and weapons is, in his own way, a champion of Khorne. He takes his limitless human potential and nobly limits himself to new ways to kill. Whether you kill with a sword or a bomb, you are killing using good old fashioned mortal strength and genius. You aren't stealing warp energy from the gods in the form of a fireball and cravenly calling it your own.
The forger of enchanted weapons, though deserving of slavery and abuse as all wizards are until the day they die, is an ideal symbol. It is fitting that spell energy be subjugated to and entombed within cold steel, just as wizards deserve to be subjugated to warriors until they lie cold and headless in the ground or else burnt to ash. The magic weapon is a symbol of might's superiority to magic.
Blood for the Blood God! Skulls for the Skull Throne!
This is awesome sadly GW had to make Khorne a hypocritical psycho serial killer.