The King is described as not looking at all like his son Dorian; he has a broad frame with a round face of craggy features and sharp eyes.
When the King was younger and before he had been taken over by the Valg, he was much like his son Dorian, always poking around in forgotten places where he wasn’t wanted and reading books no one his age should read however he was inhabited by the Valg when he was still young and it changed him.
The King is a tyrannical and sociopathic ruler who takes great pleasure in exerting his will over others. He does not appear to care about anything other than himself and gaining more power. He is responsible for the death of Celaena's parents and countless other people. He caused magic to disappear from his realm and slaughters anyone affiliated with magic or magic users. He is feared by almost everyone in his Kingdom. His name is unknown throughout the whole series, but it is almost certain, that the king was born into the Royal House of Havilliard.
When the King was younger he found the Wyrdkey hidden in Elena's tomb and brought it to Morath. Perrington took the King under the Keep to show him the crypt, even though it was forbidden. But the King opened it with the key and Erawan came; he took Perrington’s body - and let his minion take the King's body.
When Aelin was a child, the King visited Terrasen shortly before the takeover of the country. While a feast was held the King or the human inside him tried to influence Aelin to use her fire to kill him and the Valg living in him.
Shortly before his Conquest of Terrasen, the King of Adarlan issued a proclamation claiming that magic was an affront to the Goddess and her gods as it tried to imitate their divine power. As a result, he outlawed magic and led the purge of magic from Erilea, burning ancient books, sacred sites, and even magic practitioners themselves.
The human still inside the King was scared of what would happen when the Valg discovered Dorian's powerful magic so he built the Wyrdstone Towers to rid the continent of magic, however, using his own blood in the spell made his line immune and eventually, Dorian's magic came out.
The King of Adarlan hosts a competition in order to appoint a King's Champion, who would perform his dirty work, inviting twenty-three of his council members to each sponsor a would-be Champion.
The King continued his mission to conquer Erilea.
The King ordered Celeana to assassinate Galan Ashryver, and he possessed Dorian by forcing him in a Wyrdstone collar. The human in him tried to stop that from happening.
More to be added.
- ↑ Throne of Glass by Sarah J. Maas: Chapter 5, pg. 31