The Writer glimpsed it in his journeys through the various hells, but he paid no heed to it. His tale was about the afterlife and the punishments therein, not the arms and armor of the Darkness.
The grave robber grinned as he left the royal barrow, his pockets full of stolen gold, and dressed in a helmet and chainmail shirt stolen from the now naked, decomposing body of the king. The explosion that followed ten seconds after he stepped into the sunlight wiped the smile from his face and blew his body into pieces. Had he studied metallurgy, he would have known that the armour was made of pure Orthacarium and he would have left it alone, and escaped the barrow with his life.
Khor are a monsterous and violent race. Within five years of being born, they grow to about half human size and are very, very inteligent. As they get older, they get larger... unfortunately they become less intelligent. After their adolecesence (about seven years), they grow to human size and are of a low human intelligence. As they age, they grow larger, slower, and stupider. Most of them end their lives 3 to 4 meters in height. Khor have been reported upto 10 meters tall, though those elder giant Khor do little but hit anything that disturbs them.
As they age they get larger, they don't seem to ever die of natural causes.