Place of Birth
Kurt Marko (father, deceased), Marjory Marko (mother, deceased), Sharon Xavier Marko (stepmother, deceased), Charles Francis Xavier (Professor X, stepbrother), Cassandra Nova (stepsister, deceased), Lilandra (ex-sister-in-law), David Haller (Legion, stepnephew, deceased)
The Juggernaut originally possessed untold mystical power which enhanced his strength to an unknown degree and made him a seemingly irresistible, unstoppable being. Once he began to walk in a given direction, no obstacle or force on Earth was able to stop him. Some obstacles, for example many tons of rock, or forces such as plasma-discharge cannons slowed his pace considerably, but nothing stopped him permanently from advancing. The Juggernaut was, however, vulnerable to magical forces of sufficient strength.
Besides giving him vast superhuman strength, the mystical energy of Cyttorak gave the Juggernaut an extraordinary degree of resistance to all forms of injury. The Juggernaut could also shield himself even further from injury by mentally surrounding himself with a force field. Enveloped by this field, the Juggernaut had been seen to survive the fiery explosion of a truck transporting a huge quantity of oil without any injury whatsoever. The Juggernaut could survive indefinitely without food, water, or oxygen thanks to his being sustained by his mystical energies alone.
In the past, the Juggernaut has temporarily possessed telepathic abilities and certain mystical powers, all of which he has since lost. Recently, however, the Juggernaut has been stripped of this mystical energy, including his personal force field. He still possesses superhuman strength, endurance and durability due to years of absorbing the mystical energies of Cyttorak, but the current upper limit of these traits is as yet unknown.
As you all can see, Charles Xavier is Cain Marko's step-brother. Marko's mother died and Xavier's father died when they both were younger and then their parent's married each other. (Crazy connection huh?!)
Cain and Charles were drafted into military service and served in the same unit. At one point, Cain went into a cave that housed the lost temple of Cyttorak, a powerful mystical entity. Inside the cave, Cain found the Crimson Gem of Cyttorak and after he touched it he was transformed by the gem's mystical energies into a human juggernaut. After he was turned into the Juggernaut, Cain was buried by a cave-in. Charles believed his stepbrother had died. (To learn more about the above highlighted character and item just click on the them, but know that there is pretty much nothing currently written about them on the Marvel.com website.)
Here's an interesting fact: During The Hulk's attack on the X-Men during World War Hulk, Juggernaut was transported by Cyttorak to where the Hulk was. The Hulk beat Juggernaut, but then later the Juggernaut became fully powered and engaged the Hulk again to a stand still. (To learn about the Hulk, just click above.)
Juggernaut started out as evil, but has recently embraced his good side. He eventually joined his stepbrother's, Professor X, X-men. When doing this he changed his outfit from the red-brownish to his black/grayish and yellow outfit. (The black/grayish and yellow outfit is shown in two of the above posted pictures.)
The Juggernaut wears a helmet fashioned from an unknown mystical metal found in the Crimson Cosmos dimension of Cyttorak. The Juggernaut subsequently fashioned a skullcap from scraps of the metal used to construct the helmet. The Juggernaut originally wore a suit of armor that he could summon around himself at will from the Crimson Cosmos. After being stripped of his powers, the Juggernaut took to wearing a suit of armor that resembles his original but is fashioned from unstable molecules. Without his helmet and skullcap, the Juggernaut is vulnerable to psionic attacks against his mind.
The Juggernaut had a short-lived romantic relationship with Jennifer Walters (She-Hulk), who is Bruce Banner's (Hulk) cousin. (To learn more about the Juggernaut and his relationship with She-Hulk and to about the evil to good flip-flopping of Juggernaut, click on the following website, http://www.marvel.com/universe/Juggernaut. Note: If you decide to go to the She-Hulk bio page you will want to block images because the first image shows the She-Hulk in a very risque and tight-fitting outfit.)