Crimson King

"All hail the Crimson King."

- The Crimson King

The Crimson King is the overarching antagonist of the entire Stephen King multiverse, and the main antagonist of the Stephen King novels Insomnia and the Black House, as well as the main antagonist in the Dark Tower series. He is a trans-dimensional demon/were-spider who wishes to remake the multiverse in his own image so he can rule it all in chaos.

Personality
The Crimson King himself is portrayed as an intelligent creature who is bent on destroying the multiverse by knocking down the Dark Tower, so he can remake it in his own image. Despite his intelligence, over the course of the book series, he seems to grow more insane and his homicidal urges seem to happen more often.

He tends to promise his allies power and prestige, but also tends to demand that they serve him with no questions. He is shown to have no problem of having anyone including young children murdered, as he is known to of ordered his servants to have children murdered in order to secure his plans go without fail.

The Crimson King also seems to be a rather pretentious and paranoid creature who fears a prophecy that he will meet his end to the point he eventually kills all those around him and later himself, so he can become an undead abomination that retains not only his mind but powers. This is done so no conventional means could kill him and he could continue his mad quest to remake the multiverse into a chaotic void to rule for all eternity.

Biography
He is described as a demonic creature born of chaos who rules over evil and evert demonic creatures (with some notable exceptions such as Tak) as their "king" in several universes of the Stephen King collective multiverse. He is the ultimate enemy of the protagonist of The Dark Tower, Roland, the Last Gunslinger.

In the Dark Tower book series, the Crimson King enslaves many powerful psychics known as the Breakers to destroy the Dark Tower, an eldritch monument that is the base of every existing universe, so that everything in existence would collapse with, being replaced by a chaotic darkness that he could rule and manipulate forever.

The Crimson King first appears as a menacing, dangerous and intimidating Dark Lord, but he fittingly becomes more and more insane as the story progresses, ultimately murdering everything around himself and ultimately himself. After his demise, he becomes an undead abomination who attacks the protagonists and is ultimately defeated as he is erased from existence through a magical picture that represents him being created then erased.

According to supplementary works about the series, the Crimson King was born of a union between a female elder demon of the primordial 'Prim' (the chaos/nothingness before the cosmos formed) known only as the Crimson Queen and the difficult-to-place icon of Roland's world, a male human named King Arthur Eld. Arthur Eld was seemingly the first unified ruler of the world since the Great Old Ones had caused an apocalypse on many levels, a destruction so thorough, all was thought lost. Whether Eld was supposed to have any connection to the legendary and historical Arthur of our time and place is never spoken of. Celebrating his united crown, Eld and his court threw a celebration that was stated to be open to anyone. Using this opening, the Spider Queen demon and her followers assumed pleasing Human forms and reveled with the Human celebrants, with the Queen seducing Eld and producing the Crimson King. Since Roland is also a descendant of Eld, the two are distantly related, and he even referred to Roland as his "cousin".

The King supported the rise to power of pawns such as Randall Flagg and John Farson in his quest to drive All-World to its final ruin, and the collapse of the Tower. Through a particularly twisted and convoluted scheme, he caused Susannah Dean, apprentice gunslinger under Roland, to become impregnated with a child who would be both his own and Roland's, giving this child access to the Dark Tower, the King could never have. The child (tellingly called "Mordred") was all his fathers were, squared and cubed, but their flaws were also magnified in him, and he in essence self-destructed.

This last setback seems to be what finally drove the King irredeemably insane. Even after his erasure, the King endured as a bodiless wraith, reduced to a set of eyes, becoming his own sigil, the "Crimson King's Eye" or "Crimson Eye". Because Roland's journey was revealed to be a cyclical one, it is unknown whether he defeats the King the same way in each iteration. While a creature of pure nightmare, he is able to be defeated by mortals, and his downfall embodies Stephen King's idea that while true evil seems alluring and seductive from a distance, up close it is usually quite pathetic.

Trivia

 * The Deadlights.jpg of the Crimson King's many deadly arsenals at his command is writhing bright orange lights called "Deadlights", a dangerous and eldritch form of energy, which composes the very life essence of another inhuman Stephen King villain known as It/Pennywise the Dancing Clown.
 * The SCP Foundation's universe includes a similiar eldritch demon called the Scarlet King, who is presumably based on the Crimson King.