During a holiday in Europe writer Charles Bentley acquires an old typewriter. Everything he writes about with this item... Comes to life! X is a figment of Charles Bentley's mind, what the Tibetans would call a 'tulpa'... A living breathing phantasm. X becomes alive and wrecks havoc among the city, constantly following Charles wherever he goes. In hope of destroying X, Charles destroys the typewriter. X then stops in his tracks and once more disappears from site. It seemed that X had finally been defeated.
X was created by Stan Lee
and Jack Kirby
and first appeared in Tales To Astonish #20
Mayor Story Arcs
Some years later, the evil entity known as Nightmare
conjured X to terrify a young Peter Parker
in his dreams when he was on a fishing trip with his Uncle Ben.