Randall Flagg

"You expected Charles Manson at the very least, didn't ya?"

- Randall Flagg

The most recurring and without a doubt, the most important villain of the entire Stephen King mythos, Randall Flagg is following King's own words, the best villain he created, whom he had in mind since he began writing. Randall Flagg goes by many aliases including Walter O'Dim, and Marten Broadcloak, but his real name is Walter Padick.

History
Within the novels, Randall Flagg was given to a mill owner and his wife to learn the ways of man. However, at age 13, he grows bored and burns down his house and seeks to find his real father, Maerlyn. He is raped by a stranger the next year. Flagg becomes something of a "quasi-immortal" demon upon having learned the ways of Dark magic from his father once he finds him.

Flagg has appeared in multiple works, always as a powerful and charismatic embodiment of evil. It was also implied that another Stephen King villain known as the unholy demon He Who Walks Behind the Rows in Children of Corn, was an avatar for Flagg, who shares similarities with the biblical demon Legion. Flagg was first introduced in The Stand, where he represented the concept of evil and stood in opposition to Mother Abagail, who represented good: the two fought for control over the survivors of a world plagued by disease. He made a second appearance in The Eyes of the Dragon where he plans to put the medieval city of Delain into chaos. He appears in the Dark Tower series where he goes against Roland Deschain in reaching the Dark Tower so can he get to it first and use it to become a god.

Flagg's main purpose seems to be the bring about the end of civilizations by spreading destruction and sowing conflict. He has many supernatural powers by which to achieve his goals: such as necromancy, prophecy and the ability to look into the predatory nature of man and beast.

He ultimately meets his end when Roland's half-son, Mordred, kills Flagg for trying to manipulate him.

Appearances in other media
Randall Flagg appears as the the main antagonist of the 1994 TV miniseries The Stand based on a Stephen King novel of the same name while his enemy Mother Abagail also appeared. He was portrayed by Jamey Sheridan.

Randall Flagg who also can take form of a raven, was present when the Captain Trips flu, a deadly virus began and swept across the United States and soon the entire Earth in a matter of weeks, eliminating 99.4% of the planet's human populace.

He later chosen and raped his new "bride", Nadine Cross, whom he has been visiting in her nightmares. She soon turned on Randall while having remaining feelings for the man named Larry she met in New York. She committed suicide by taking a jump off the balcony of Flagg's penthouse in Las Vegas, killing not only herself, but also Randall Flagg's unborn child she was pregnant with, not long she replied her final words to the monster, "your seed is cold".

The Dark Tower (2017)
He appears as the main antagonist of the 2017 movie The Dark Tower, based on the book series of the same name.

He was portrayed by Matthew McConaughey, as his first villain role.

Sometime before the events of the film, he killed all of Roland's men and then during the events of film, he killed his father by telling him to stop breathing. However, Walter's powers didn't work on Roland since Roland was born with a special type of power that can deflect demonic powers.

When Walter found out that Jake had a psychic mind, he sought to find the boy to destroy The Dark Tower and rule over the other worlds. In the film, O'Dim kills Jake's stepfather and mother by telling his stepfather to drop dead. He later incinerates Jake's mom Laurie. About ten minutes into the film, Jake returns back to Earth to find his dead father on the floor and his mom's ashes on the floor and breaks down. Walter is able to abduct Jake by confusing Roland by talking to him. Walter taunts Roland by telling him about his dad and how he could have saved him. Roland is furious and tells Walter to face him.

Jake is able to use his mind to help Roland find him. Roland kills all of Walter's men before confronting Walter himself. Walter and Roland have a brief fight with Walter telling him to come on! Roland starts shooting at Walter, who blocks the bullets with telekinesis. He picks up rocks and throws it at Roland as Roland ducks it and shoots some more bullets at Walter, Walter makes a trick and picks up glass and throws it at Roland, a shard of glass becomes stuck in Roland's hand, and he hides behind a brick wall as Walter taunts him. Walter is able to throw a I-Beam on top of Roland and cover him with rocks, injuring him.

As Walter has a fireball in his hand and is going to kill Roland by burning him. Jake recites the Gunslinger's creed as Roland recovers and gets back to his feet. He shoots at bullet at Walter who is able to block it, however, he shoots another bullet that ricochets off the wall and hits Walter in the stomach. Roland reloads his gun and shoots Walter several times in the chest before shooting him in the head, finally killing him and avenging Jake's mother and Roland's dad. We briefly see Walter's body as he had a bullet hole in his head.

The machine is destroyed and The Dark Tower is saved.

Quotes
"Wait a minute, son. Wait a minute. You ain't seen nothin' yet."

- Randell Flagg demonstrating his demonic magic to Lloyd Henreid.

"Please to meet you Lloyd, hope you guessed my name (Lloyd: What?) Oh. Nothing. Just a little classical reference. Actually, my name is Flagg, Randall Flagg."

- Flagg introducing himself to Lloyd.

"You can't stop what's coming, death always wins."

- Man in Black to Gunslinger

"You're crawling your way out of the darkness. Did you ever tell the kid who walks with you dies by my hand?"

- Man in Black to Gunslinger

""You really think you can stop me, Gunslinger?""

- Man in Black to Gunslinger

Trivia

 * Randall Flagg is regarded as Stephen King's most popular villain. As such, King himself regards him as the greatest villain he ever wrote.
 * Many fans suspect that the dark form at the end of The Long Walk to be an incarnation of Randall Flagg somehow.