DNA samples taken from Project Cadmus scientist Dr. Curt Connors were stolen by an unknown villain and spliced with the DNA of several reptiles. The result was the savage monster known as King Lizard. He was captured by Spider-Boy and kept in the containment cells at Cadmus.
However, during a battle between Spider-Boy and Bizarnage, the power array to King Lizard's cell was broken. During his escape, King Lizard crashed into Hank Pym's lab. Exposure to size-altering Pym particles caused him to grow to giant size. In order to stop him, Spider-Boy managed to fire a white dwarf star device he took from Ray Palmer into King Lizard's mouth and shrunk him to subatomic size.
King Lizard's powers are derived from various reptiles he was created from, including
- The wall-crawling abilities of a gecko
- The strength of a Komodo dragon
- The underwater capability of a saltwater crocodile
- The camouflage ability of a chameleon
- The durability of an alligator snapping turtle