The dwarfs are the most attuned to their tradition. They also have the most complete records of their history, although the records were fragmented and scattered, leaving very little of what happened before the cataclysm. One such piece of history is currently debated on if it is history or myth. This is the tale of the ruined king.
The ruined king's name is purposefully forgotten, as both a warning and a precaution. The tale goes as follows: In the year 385, King █████ of house ████████, was crowned king. Early in his years as ruler he began the projects that would lead to the expansion of the Northern and Southern cities. Wherever there was conflict, █████ acted quickly and effectively, which made him quite popular among his people.
Decades later, █████ was given a gift fit for a king, A blade unlike any other. The ████████'s were already known for they're martial prowess, but █████ was quite exceptional with a single handed blade. This blade however seemed to make █████ quite powerful, the stronger his foe, the more powerful he appeared to strike them. Those who had dueled the king in honor combat confirm that the greater in health they were when fighting him, the stronger the blows he would deal. A few veteran gladiators even swore although █████ was quite the skilled swordsman, the blade was what was striking them with such ferocity.
King █████ grew tired of these accusations as it dishonored his skill as a warrior. In the secret of night he paid a visit to the blacksmith who made the weapon. When he arrived at the home of the blacksmith, he only discovered that he and his whole family had been burned to a crisp, leaving only their chard skeletons. Because of his secrecy in the meeting of the family, people suspected that he had killed the family and burnt any evidence of the crime. This was only the beginning of King █████'s problems. Attempts were made on his life, and King who once stood for everything good, lawful, and honorable started to crack; first into chaos, and then evil. The king was a shell of his former self, always sure that anyone and everyone was out to kill him. The dwarven people noticed the king lash out against anyone who even spoke to him in a snarky way, whereas before he simply would have laughed it off and replied with something snarky in return.
The dwarven people and the house leaders that made up the council, including even his own family house, began to speak openly about the king's transgressions, and how he must pay for them. Little did they know that █████ had already made preparations to leave the kingdom. He gathered all male figureheads of house ████████ to meet him in his throne room. Clinging tightly to his blade, he told all of them that although he felt could not trust them, they were all he could trust even a little. █████ told them he felt he was near death, and in need of a burial sight. He knew the council would not permit him to be entombed with the kings of the stone, so he planned to make his own tomb, in the open topside where no one could find them, and all of his house would follow him. Those who rejected his proposal, █████ slew there in the throne room and declared himself the new figurehead of the families of traitors. Before the next day's end, all but one of house ████████'s was gone from the great kingdom. The one left behind was █████'s daughter, ███████, who due to her Father's actions as king, and the now disgraced house ████████, remained unmarried and childless for the remained of her life. Serving only to break tiebreakers in the council, and ensure that her families history was not erased. This tale however is all that remains of their history.
There are historical evidences that back up this myth. The first is that in older records there was a ninth house that acted as a tiebreaker in the council, similar to the role of the daughter at the end of the tale. There is also an few accounts of the house being banished by the other eight, due to treacherous deeds, but no where does it indicate that the house left willingly as the story dictates that they did more or less.
However, there is much more evidence that this may be a myth entirely. The first is that there is almost no pre-cataclysm history to the house in any records, public or private. Even though both the dwarven civil war and the cataclysm caused significant damage to the history, every house has at least a genealogy leading to far before the cataclysm, this supposed ninth house has no such records; only that a ninth house did in fact exist at one point, but their reasons for leaving were widespread treachery, not the actions of a single ruined king. There is also no account of a blacksmith being found dead in his own home, it simply odes not exist in any house's records; and if the king was suspected of committing the deed, the family would certainly make sure that those records were never lost or forgotten. Finally to top it all off, the hill dwarfs have found no such tomb, or even ancient dwarven remains in the years that they have been topside.
However, that does not stop the debate of if this king did exist. Those who believe that the ruined king did exist explain that no one has found it because they succeed in creating the tomb, the atrocities that happened afterwards we'll never know until the tomb is found.
All dwarven children under the mountain know this tale, or at least a variation of it. A warning to never go topside or you shame your house and lose your honor. Due to this many believe the myth to be simply that, a myth to scare children of disgracing their house, and to be cautious of damaging another person's honor.