Phaesti.
A world close to the Eastern Fringe, choked in dust and ash, and wracked by unstable tectonic activity. Life is harsh and unforgiving, and the planet's sparse population exists only because of its abundant minerals and ores.
While the Imperial settlers established great walled cities, the ash wastes are populated by tribes loyal to primitive gods and dark powers anathema to the Imperium. They live to fight and do battle in the name of their primal deities. Some recognising the greater power behind their simple idols, and revel in the worship of Khorne, shedding blood and taking skulls from their rival tribes.
Among the strongest of these tribes is the Haenthjarling clan. The Haenthjarlings pride themselves in being Khorne's most dedicated killers, and believe that for a warrior to kill his enemy with a weapon he has not made himself is dishonourable to the spirit of the blade he wields. The clan has established a major stronghold on a hill close to one of Phaesti's most notorious volcanic hotspots, the better to mine for metals and precious stones to forge their blades and decorate them in manners pleasing to the weapons' spirits. Within their stronghold, fathers teach sons how to forge a sword, how to sharpen an axe, and how to kill an enemy; and when they march to war, it is in an impressive formation, each warrior clad in heavy plate armour and carrying a shield decorated with icons of Khorne. They believe that in covering themselves in armour, they may live to eventually claim more heads and spill more blood for their god than a warrior who eschews its protection.
The Haenthjarlings have a rich oral history, but one of their most famous legends stems from events one thousand years ago. The legend says that Heidar, chief of the tribe and foremost among the settlement's blacksmiths, was approached by an emissary of Khorne and asked to create eight swords for the Master of Skulls himself. Heidar was given a year to produce the weapons for the emissary, and over the course of that year he sought out the finest iron and the best gemstones to use in their creation. When the time came to finally forge the swords, Heidar laboured in his forge for days on end, working without cease until his weapons were flawless and impeccable. Heidar inscribed the swords with runes of battle and strength, each one marked perfectly so that it did not mar the beauty of its blade; equally, though the swords were richly adorned with gemstones and icons, Heidar carefully ensured that the swords were beautiful rather than gaudy, and not rendered ineffective by their decoration.
Finally, Heidar was once again approached by the emissary, who could not help but admire the fine craftsmanship of the blades. The emissary revealed his purpose to Heidar; in testing him, the emissary had succeeded in finding the greatest smith to work as a forgemaster in Khorne's foundries. For his efforts in the mortal world, Heidar would be rewarded by being able to forge weapons for the armies of his god; and to Heidar this was the greatest boon the emissary could give him. Heidar would earn immortality as a forgemaster of Khorne and be renowned as the best smith in his world's history.
Immortality had its price, though, and Heidar listened dumbfounded as the emissary continued to speak. In order to earn his immortality, Heidar had to sever his ties with the mortal world in a sacrament of blood with Khorne himself. Gathering the eight swords to him, the emissary ordered Heidar to take up his own sword and slaughter his own tribe, beginning with his own family. Although Heidar did so willingly, his screams of grief and shame echoed through the Haenthjarling lands as he began to destroy his own life piece by piece. By the time the eighth Haenthjarling head had fallen to the ground, however, Heidar was gone, the eighth kill symbolic of his new allegiance.
Of the eight swords, only one remains. Given as gifts to Khorne's champions, the blades were taken and destroyed by their enemies over the course of a thousand years until seven of the eight swords were undone. In his rage Khorne recovered the body of his eighth champion, still holding the last sword, and had it interred in a shrine on Phaesti itself. Whether the sword still remains is not truly clear, as is whether it truly existed in the first place, but nonetheless countless champions have since tried to recover it. Though all have failed, the legend of the Sword of Heidar still draws those who would seek Khorne's favour, and those who would destroy the weapon for good.
(More to come)