He was responsible for much of the architecture found throughout Hallownest, most of it bearing a Hallownest Seal. He also built the stagways and the trams.
When the Radiance tried to be remembered again after being almost entirely forgotten, she ended up causing the Infection. To combat this, the Pale King came up with the idea to use a Vessel to seal her away. These Vessels are the children of him and the White Lady, born in the Abyss with Void inside of them.
Three bugs were asked to become Dreamers to form seals on the Temple of the Black Egg which would contain this Vessel. One of them, Herrah, only accepted his proposal if the Pale King had a dalliance (sexual relationship) with her which would result in a child; this child ended up being Hornet.
Nevertheless, the chosen Vessel, the Hollow Knight, was unable to contain the infection for eternity due to their purity being misjudged. The Pale King raised the Hollow Knight and formed a bond with them, which may have resulted in their "tarnishing".
At a certain point, after the Infection reappeared, the Pale King and White Palace disappeared.
Art by 太陽無明 on Twitter /AgentDrago en DeviantArt/eternal kingdom doodles/uknown
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