The Kobold King was a white kobold of unusually high intelligence and magical capability. He ruled over several tribes of black, red, blue and green kobolds who had been displaced from their original territory, the Great Cedar Forest, by the goblins. When his warren in the Golden Fields was raided by the Pathfinders, he was killed; Ru delivered the final strike to the Kobold King, becoming the Kingslayer.
The Kobold King was wearing a magical necklace, which was taken by the Pathfinders upon his defeat. His crude crown, made of smelted coins, now rests on the wooden elf statue in front of Ned's General Store.
The Kobold King was called as a witness against the Pathfinders when they faced the Demiplane of Judgment.
The Orc King knew the Kobold King personally as both were born inside the wall and sought a better existence beyond the constraints of a human-centric civilization.