Real Name/Alias: Cain Marko, Captain Universe, Kuurth: Breaker of Stone

1st Appearance: The X-Men #12, July 1965

Place of Origin: Berkeley, California

Profession: Mercenary

Affiliations: Brotherhood of Mutants, X-Men, Thunderbolts

Partnerships: Black Tom Cassidy

Created by: Stan Lee and Jack Kirby


  • Superhuman strength, stamina, and durability
  • Invulnerability via mystical force field
  • Immunity to mental attacks via his helmet

Synopsis of First Appearance: “The Origin of Professor X!”

At Xavier’s School for Gifted Youngsters, Cerebro initiates an intruder alert.  The X-Men remove their street clothes, don their uniforms, and make their way to Professor X’s study to learn about the intruder.  The professor related to his pupils that the intruder is exceptionally powerful and orders the team to put up defenses around the mansion.  Together the team creates an ice wall, a live wired lined trench, and fence posts lined with grenades.  With defenses in place, the X-Men return to Professor X only to learn that the intruder is in truth the professor’s brother.

Xavier explains to his team that his father, Brian Xavier, was nuclear research scientist who died during a nuclear bomb test in New Mexico.  At his father’s funeral, Dr. Kurt Marko came to console the professor’s mother, Sharon.  Xavier knew that Marko’s actions were not out of nobility, but his desire to claim Brian Xavier’s wealth, position, and property.  Over the years, Marko had become extremely envious of these things.

Marko married Sharon and moved into the mansion, but soon after he became extremely verbally abusive to Charles and focused only on his work.  Also his true intentions for marrying Sharon became evident over time.  One day, Marko’s son, Cain from a previous marriage, came to the mansion after being expelled from another school.  Cain was a cruel, angry, and nasty boy who took his frustrations out on his step brother Charles.

Cain breaks through Iceman’s ice wall and interrupts Professor X’s tale.  Warning aside, Professor X continues his tale and explains how one day Cain came to the mansion looking for a financial sum from his father, and he responded that he did not give handouts.  Cain then insinuated that Kurt had been responsible for Brian Xavier’s death, a charge Kurt vehemently denied. Upon hearing Cain’s claims, Charles confronted both his stepfather and stepbrother. The moment everyone expected had finally come and Cain fires the opening salvo, throwing a container of chemicals at Charles.  Kurt intercepts the volley attempts to stop the mayhem by throwing the dangerous concoction of chemicals to the floor, which results in an explosion and fire.  Kurt grabs the boys and runs out of the lab but is mortally wounded.  Kurt begs Charles to believe that his father’s death was only an accident.

As Cain reaches the second barrier with the electro-magnetic force shield and live wire, Professor X continues to relate his story to his teenage pupils. Professor X learns in adulthood that his mental powers give him an advantage over others academically and athletically and decides to no longer use his powers for such purposes.  The trophies and accolades Charles had earned using his powers angered Cain and the two had a fight, a fight Charles won due to his mental powers by knowing what Cain was going to do before he did it.  Next, Cain tried to scare Charles by driving a car off a cliff.  Cain bailed, but Charles survived using a mental shield to protect him.

Back outside, Cain has busted through final defenses of live wires, a force barrier, grenades and gas traps.  Iceman ices up the broken window in the professor’s study.  This gives Professor X the time to tell the last part of his story.  When both Charles and Cain had grown up, they both enlisted in the military during the Korean conflict. During an intense battle, Cain deserted and ran into a cave for protection and refuge.  Charles ran after him and both men stumbled upon the lost temple of Cyttorak.  Seeing a crimson gem on the altar, Cain grabbed it and read aloud the inscription on the gem. Instantly Cain was transformed into a hulking beast of man. Seconds after Cain’s transformation, the cave was bombed by conflict’s combatants.  Charles escaped the cave, but Cain was left buried under tons of boulders inside the cave.

With this story complete, Professor X realizes that Cain has finally escaped his prison like cave in Korea and has come to take his revenge on his brother.  Cain has destroyed all the mansion’s defenses, and all that is left is an impervious steel plate attached to the front door.  Cain easily destroys the door and knocks the X-Men back with little effort.  Cain reveals himself for the first time in years.  Professor X looks at his brother, clothed in special mystical armor and calls him a human Juggernaut.






Lee, S.; Thomas, R.; Kirby, J., Werner, R., & Roth, W. (2015) X-Men Epic Collection: Children of the Atom. Marvel Comics.

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