Edward Whelan was found roaming the streets of New York by Baron Helmut Zemo. Whelan subjected himself to Zemo's genetic experiments, which granted him superhuman strength. However, in the process of the mutation, he manifested a rat-like physical appearance, and was called Vermin. It was Zemo's plan to use him to kill his nemesis Captain America, once and for all. Although, the cunning Captain was able to defeat Vermin.
Vermin later appeared in the sewers of New York, when the mysterious female Kraven was holding Vin Gonzales hostage there, thinking that he was Spider-Man. Vermin attempted to run the unwanted intruder out of the sewers but failed, due to the interference of the real Spider-Man dressed in the costume of Daredevil. Vermin escaped into the tunnels of the sewers. He later ran into the real Daredevil who he led to Spider-Man and Gonzales, who were now both captives of Kraven. Vermin battled the female once more, and it appeared that he would be the victor, although, he was last seen badly beaten on the floor of an unknown location, at the feet of Kraven's mother.
