Origin

The creature was created when Curt Connors' lab assistant Aldo tested a new variation of the serum to cure Curt, on a piece of a tail of Connor's Lizard form. Right before his eyes the tiny piece crew to humanoid sized and form and attacked Aldo. Lizard then escaped to the wild.

Creation

This lizard was created during the Planet of the Symbiotes story arc spanning several special issues for Spider-Man titles. The lizard was also used during the Marvel/Malibu crossover event Black September, and in Marvel Versus DC crossover.

Major Story Arcs

Growing Pains

Something pulled Lizard to New York, and as he moved towards it he left bodies in his wake. Lizard attacked a party, but before he could achieve his goal, he was attacked by Armstrong and Scarlet Spider and was forced to retreat by burrowing into the ground. Soon after that, he went after Dr. Noah Purl at Empire State Hospital. The Lizard attacked Dr. Purl, but before he had a chance to finish him off, Scarlet Spider interfered again. Lizard lost his tail in the scuffle, and made a run for it. He took shelter in the zoo in Central Park to recover. His respite was however brief as both Scarlet Spider and Armstrong once again came after him. In combination of severe beating and cold from fire extinguishers the Lizard was subdued and wrapped up in the webbing ready to be shipped of to the Vault.

Ultraverse

During the transport, the helicopter was hit by something, and Lizard broke free. He attacked the one responsible, but another Spider-Man came to his defense. The fight was long and Spider-Prime joined in, this was for the benefit of Lizard however, as Prime knocked out Spider-Man by accident. The fight is suddenly interrupted by a portal, which spits them out in mid air somewhere in Amazon. When he woke up, some machines were approaching him, and the Lizard attacked them. While fighting the machines, he lost his hand and retreated, but ran into Prime again and they fought again. During the fight, Prime tried to use some totem to make the Lizard remember who he was, but Prime didn't realize that this Lizard was not Curt Connors, like everyone had assumed up to this point. This Lizard only wanted more power, and manged to use the totem to portal back home.

Lizard vs Lizard

Back on Earth-616 the Lizard landed on a cop car. During the rampage that followed, the Lizard was once more confronted by Ben Reilly and soon after by Spider-Man. Spider-Man then reveals that they are not fighting Curt Connors to Ben, as he was just next to him in a hospital when they saw the Lizard. Lizard managed to get away from them when they were distracted, and went after Curt Connors, who had flown to his home in Florida. When the Lizard attacked Curt in his home in front of Billy Connors, it was a catalyst for Curt Connors to turn back into the Lizard himself. Connors being no mere beast easily killed the Lizard.

Alternate Versions

The Lizard was spotted in Marvel Versus DC where Batman tracked his movements, but his attention was drawn away from Lizard.