Will a Justice Leaguer become a Teen Titan? If that reversal has ever been done – Teen Titans initially being the JLA’s sidekick club – I do not know the occasion, no matter what continuity we are discussing.
As everyone not under a rock knows, as of September 2011 Cyborg is being featured as one of the main characters in a new Justice League ongoing series written by Geoff Johns and drawn by Jim Lee as part of DC's New 52 relaunch. Johns in a Newsarama interview has said of Cyborg, “He represents all of us in a lot of ways. If we have a cell phone and we're texting on it, we are a cyborg -- that's what a cyborg is, using technology as an extension of ourselves.”
In the ongoing Justice League storyline takes place five years in the past and retcons the team’s origin, Victor Stone appears as a high school football star who is heavily sought after by a number of college scouts. Apparently, though, he has a distant relationship with his father. After winning a big game, Victor is shown calling his father and angrily telling him that he broke his promise and missed yet another one of his son's games. (Familiar, gang?)
Later, Victor appears at S.T.A.R. Labs where his father works. (The scientists appear to be working on the alien technology that Batman recovered from the Parademon.) Victor ensues in another argument with his father and tells him that the scouts were there to give him full scholarships to college. When asking if his father will ever appear at any of his games, his father replies a somber "No." Just then the alien technology explodes, killing the scientists and destroying most of Victor's body as which Victor's father looks in horror.
With all this said and despite being retconned into a founding member of the Justice League, Cyborg's history with the Teen Titans is apparently still intact. In Red Hood and the Outlaws #1, he is mentioned as one of Starfire's past teammates during a conversation with Roy Harper.
The Martian Manhunter has also been named as a past League member in Stormwatch. Boy, when this five-year origin story concludes and returns to present day, Geoff Johns is gonna have some ‘splainin’ to do!
But I digress …
In original continuity, Victor was the son of Silas and Elinore Stone, a pair of scientists who decide to use him as a test subject for various intelligence enhancement projects. (How romantic … in a Frankenstein kinda way.) However, while these treatments work and Victor's IQ grows to genius-levels, he begins to resent this treatment and strikes up a friendship with Ron Evers, a young miscreant who leads him into trouble with the law.
This is the beginning of a struggle where Victor strives for his own life engaging in pursuits of which his parents disapprove, such as athletics. In addition, Victor still keeps bad company that leads him into incidents such as when he is talked into participating in a street gang fight in which he is wounded. For the most part, however, Victor still has a largely normal life under the circumstances where he also refuses to follow Evers' grandiose plans of racially motivated terrorism.
When he visits his parents at work at S.T.A.R. Labs, an experiment in dimensional travel goes horribly wrong when a massive gelatinous monster crosses over an experimental portal and kills Elinore. The creature then turns on Victor and severely mutilates him before Silas manages to force the creature back through the portal.
To save his son, Silas outfits him with experimental prosthetics of his own design. However, the equipment cannot be worn inconspicuously, and thus Victor is horrified to see much of his body, including part of his face, replaced with sheer metallic limbs and implants. Although Victor wants to die at this shock, he eventually adjusts enough through his resulting physical therapy to control his implants with suitable skill.
Upon release from medical care, he finds his life is seriously inconvenienced with the fearful reactions of the public at his implants (you mutants understand); even his girlfriend Marcy Reynolds rejects him. (Now that, I understand, lol.) In addition, he is also disallowed participation in athletics not only for his implants, but also for his poor grades, which are the result of inattention prior to his accident (rather than a lack of sufficient knowledge) and further exacerbated by his long convalescence.
However, when his old friend Ron Evers attempts to use Victor's troubles to manipulate him into participating in a terrorist attack on the United Nations, Victor finds a new purpose as he equips his weapons attachments and stops his friend in a pitched battle on top of the UN!
Of course, Victor joined the Teen Titans afterward, initially for the benefit of a kind of “support group” of kindred spirits and outsiders, and had remained with that group ever since.
Now, in the DcnU, a new Victor is taking a different road. It will be interesting to see where it takes him … although we know he and sultry Starfire will be together sometime somewhere!