Zane Yama inherited the powers of the Juggernaut from his father Cain Marko. Cain was the original Juggernaut and Zane's father but on a mission with the X-Men, Cain was lost to an alien dimension when Zane was only a couple years old. Zane was raised by his now single mother, assistant district attorney, Sachi Yama.
Throughout his childhood Zane would experience a reoccurring nightmare in which he is chased by a Juggernaut-like creature. As a teenager in high school the dream began to become more prevalent and frequent. Zane's Juggernaut powers finally manifest on a day at school when he is being persuade by the bully by the name of Miller Hallendale. The stress of the day triggers a nagging headache for Zane which progressively become more intense. As he is hiding in the school gym the headache becomes nearly unbearable when suddenly in a flash of light he is transformed from puny nerd into the hulking figure of the invincible Juggernaut.
Zane eventually transforms back to his normal self, his powers have a time limit he cannot control. He creates a costume out of pieces of his father's old stuff he finds in basement storage. He gives the costume a new silver look, ties his father's old shirt around his waste as a tribute and begins calling himself J2 as his costumed identity.
J2 was created by Tom DeFalco and Ron Frenz and first appeared in What If...? issue 105 (1998).
Mayor Story Arcs
While at a bookstore Zane Yama witnesses a horde of Asgardian Trolls chasing down Kevin Masterson because he possesses the Thunderstrike mace. Zane transforms into J2 to come to the aid and is also met by several other heroes answering too an Avengers distress beacon. A battle with the trolls leads the heroes to Asgard where they encounter Loki who is behind the disturbances. The heroes finally succeed in escaping and protecting Kevin and the mace. Upon returning to Earth, Mainframe suggests that the group unite to create the new generation of Avengers as the team has been inactive for around 10 years time. J2 is one of the four heroes that agrees to be one of the new members of A Next.
Working on his own and with the Avengers, Zane grows into the role of a hero, but not before fleeing battle after apparently witnessing Mainframe's demise. Zane appear to have a crush on fellow Avenger Stinger. Most recently in Avengers Next, J2 also develops an attraction for Thena (Thor's daughter), even risked his life to save Thena's, which definitely didn't impress the Blue Streak, who has a "thing" for J2.
Finding His Father
With the help of Doc Magus, Zane is able to locate his father. He is being held captive by the nightmare creature Nemesus in a small pocket dimension. It is revealed that Nemesus in fact had a hand in J2's origin. Nemesus was attempting to extract Cain Marko's powers for himself but a miscalculation transferred them to Zane instead. Eventually receiving the aid of the original Defenders ( Dr. Strange, Namor, and the Hulk) they are able to defeat Nemesus and his darkling creatures and return Cain Marko back home to be reunited with his family.
Powers and Abilities
Zane Yama has the ability to turn into the form of J2. In this form J2 is invulnerable and super strong. He can approximately lift (bench) 75 tons. As a result of being Juggernauts son, J2 has the ability to become unstoppable when he starts to run. Unfortunately he can only be in this form for about one hour until he uncontrollably changes in to his Zane Yama form. Like his father, J2 is also susceptible to mind attacks which lead him wear a helmet which protects his mind.