Jan's father Tarn Arrah was the leader of Trom, which had been discovered by R.J. Brande some time before. Tarn was the creator of tarnium, the element which was needed to create Stargates. Only Tarn and Jan were adept enough to create this element.
Tarn and his wife Garra were negotiating with the United Planets for membership when a squad of White Triangle Daxamites came and used their heat vision to destroy Trom. They had feared that the transmutation powers of the people of Trom would allow the United Planets to become unbeatable.
Luckily, Jan and R.J. Brande had managed to get off-planet in time, though they could do little else but watch helplessly while Trom was destroyed.
Jan and R.J. made it to Earth in time for Jan to create the tarnium needed to open a Stargate and transport the invading Daxamites to a red sun planet. Cosmic Boy invited him to join the Legion of Super-Heroes for his efforts, but President Chu blocked his induction. Jan then returned to Trom to transmute each Trommite's remains into a crystal monument.
It was while he was doing this that he was attacked, captured and then brainwashed by President Chu to kill the Legion. In a near-mindless state, and wearing an identity-concealing costume equipped with a thought screen, Jan attacked the Time Institute where he was delayed by Saturn Girl until, with her at his mercy, he hesitated, then retreated rather than following through on his orders.
Very shortly afterwards, he was let loose on the U.P. applicant planet Guron, and Chu ordered the Legion to stop him. When the team reached Guron, however, he disintegrated their Cruiser, then "disintegrated" the air around them, suffocating all but the shrunken Shrinking Violet, who proceeded to punch him hard enough not only to knock him out, but also to shatter his mask, leaving him blooded and revealed, and Vi puzzled and guilty..
He was then taken to Legion HQ for treatment. While there, a psi-scan revealed that he had been brainwashed; unfortunately, Chu had planted false evidence suggesting that Winema Wazzo was the one who had brainwashed him, and that he had seen a Sun-Eater in space. This was actually a trap whereby Chu intended to force the Legion to work alongisde the Fatal Five, only for the Five to turn on them and kill them.
Luckily, Cosmic Boy and Invisible Kid had anticipated this and Jan was recruited into the Legion Rescue squad by Live Wire. The Squad was able to save the Legionnaires and stop the Fatal Five; Jan went on to help the Legion expose Chu's plot and undo all her actions. He also saved Leviathan by transmuting the Persuader's atomic axe into cheese spread.
With Chu impeached and R.J. Brande drafted as President, the Legion were given control of their membership and Jan was inducted into the Legion, though he would soon go on a leave of absence to finish his task of creating memorials for his people on Trom.
When Violet used the Emerald Eye to grant every Legionnaires' wish, Jan's was to be invited by his parents to join them on their "journey" to the afterlife. Luckily, Saturn Girl sensed Jan's suicidal thoughts and was able to intervene before Jan seriously considered killing himself.
When the Legion encountered Mordru, they were able to keep him off-balance at first. Unfortunately, Mordru was able to adjust to the attack and he defeated the Legion and turned Element Lad into crystal. In that form, Jan was initially unable to move or speak, until his powers eventually asserted themselves enough for him to "wake up". However, he was still largely immobile and could not use his powers directly, and so was forced to sit out the Legion's battle against Mordru, until he was finally able to reassert a degree of control. He and Sister Andromeda joined the battle in time for Jan to seal Mordru's prison.
From then on, Jan was able to change his own body into various elements; however, he had trouble changing other objects unless he had transmuted himself first. These constant changes made him even more "spacey" then before, and he was constantly appearing absent-minded. One instance was when he was transmuting a wooden beam into an explosive mixture during a training exercise, which caused an explosion - but he had neglected to warn the other Legionnaires and hadn't even thought of doing so.
However, Jan proved to maintain his normal intelligence during a battle with the Composite Man, when he came up with the strategy of encasing the Composite Man in inertron and transmuting his air into knockout gas. Jan had acutely judged that the Composite Man hated his fellow Durlans so much that he would not use his native Durlan shapeshifting powers, which would have allowed him to escape from the prison easily. Instead, he tried using his acquired strength to break free, which only served to allow him to hyperventilate.
It was also during this period that Jan developed a close friendship with Monstress, even kissing her hand on Summer World. He also transmuted her green skin into orange skin, an act which caused Monstress to chastise him, but their friendship remained. He would also come to the realisation, prompted by Ferro, that he shouldn't allow destinies to occur "by default", but should actively save the lives of the injured rather than simply memorialising them.
In the Great Rift Disaster, Element Lad, Kid Quantum (Jazmin Cullen) and ERG-1 were tasked with sealing the Rift itself. They were successful, but Drake's containment suit was destroyed and Jan, KQ2, and half the Outpost and those inside it were pulled into the Rift.
Thrown outside the material universe, Jan sealed his teammates in pure Green Tromium to protect them. He spent months calculating, longhand as the computers and clocks of the Outpost had ceased to function, how to get them back into the universe proper. Eventually, he succeeded. After a fashion.
He became separated as they crossed the barrier, and while they emerged displaced only in space from their origin point, thrown into a "Second Galaxy", he landed in the same place... billions of years earlier.
Transmutating himself into Green Tromium, he drifted for a long time. Eventually, he landed on a planet, and there, disappointed at the lack of life, began to "help it along"...
Jan created many races and species, including the Kwai and the Progeny. However, his powers and his long life had caused his mind to warp - he had gotten a "new perspective", viewing all other life as mortal, short and insignificant compared to his. He created species after species, but had them "deleted" once he grew bored or displeased of them. The Progeny were his latest creation, and he tasked them to destroy all "variants" who did not fit into his ideas of perfection.
When the Legion reappeared in that part of space, Jan's memories were triggered. It was only then that he remembered them at all, and he sent his Progeny to capture them. They were brought into the Rosette, Jan's artificially created base of operations, which was actually a string of planetoids linked together.
Element Lad healed the Legionnaires, closed a lesion in Brainiac 5's brain and restored Live Wire's arm, but his new attitude and advanced power levels frightened the Legion. He also revealed that he had captured the Omniphagos, a virtually unstoppable creature which could consume almost any matter, and "fed" it to see what would happen. With it contained elsewhere, he had also opened its prison, "The Ark", which turned out to be a hard-light structure which could serve as a portal to anywhere.
Saturn Girl, Monstress and Chameleon talked to him to assess his threat. Jan mentioned that he planned to use the portal to return to UP space and "play God" there, while releasing the Omniphagos to destroy the galaxy they were currently in. When Monstress pleaded with him to stop, he noticed that he had never created her and promptly destroyed her.
He then went on to defeat the other Legionnaires, although Saturn Girl was able to distract him long enough for the Omniphagos to escape. As the Omniphagos consumed Jan, he transmuted it, binding them together into a hideous crystalline beast. Live Wire sacrificed himself to electrocute the beast, leaving Jan dead but saving both galaxies and their fellow Legionnaires.
The memory crystals that Jan had created were placed by the Legion on Trom as a memorial by Kid Quantum. Spark later added some more, electrically charged, crystals which she had found at the site of the Rosette. These crystals interacted with one another to grow a new crystalline body which resembled Jan, but had Live Wire's mind and both Jan's transmutation powers and Garth's lightning powers. The reborn Live Wire has since rejoined the Legion, while it is believed that Jan's spirit has finally gone on to complete his journey to his parents.
Powers and abilites
Element Lad could alter the atomic structure of matter. This ability was most often displayed by Jan turning (or transmuting) one element into another, though he could also transmute multiple elements at a time to create mixtures. After his transformation by Mordru, he could also transform himself into other substances, and found it easier to "transmute" other substances by doing so.
After several billion years of practice, as the Progenitor, he could manipulate matter incredibly finely and on huge scales.