When Spencer Smythe died because of his prolonged exposure to radioactive chemicals, Alistair inherited his legacy and his hatred for Spider-Man. In his first attempt to kill Spider-Man, he mistook Mary-Jane Watson for Spider-Man who was playing along with it to give Peter time to come up with a plan. Mary-Jane claimed she used a super suit built by aliens to deceive Smythe until the real wall-crawler defeated him. He then tried to kill Spider-Man again when he and Mary-Jane were trying to get her sister out of prison for helping their father in a crime. He worked for the Kingpin at first, but only after a disagreement over how to deal with Spider-Man.
After being sent to an asylum, Alistair escaped and took several other inmates along in order to build a new Spider-Slayer. After sending a series of slayers, after Spider-Man, that were destroyed by him with help from Black Cat, Alistair lured Spider-Man to his home for one last fight. Alistair modified his body with cybernetics and began a battle with Spider-Man, but was defeated and taken into custody with the other asylum inmates.
While the Scarlet Spider worked in the city, Smythe began a war with a new slayer he wanted to sell on the black market. These Cyber-Slayers, as he called them, were controlled by turning one's thoughts into the slayers' actions—and they were probably so named because the initial target was Carolyn Trainer (Lady Octopus) and her group, not Spider-Man or the Scarlet Spider.
However the Scarlet Spider ended up in the middle of things and temporarily worked with the Cyber-Slayer although Smythe was eventually brought to justice.
Smythe escaped prison and wanted revenge on Spider-Man and J. Jonah Jameson for his father's death. He made Jameson alter the stories in the Daily Bugle or he'd kill his wife and son. Spider-Man caught Smythe's trail, and followed it back to the Bugle, but was attacked by every version of spider-slayer ever sent after Spider-Man plus a pair of new ones, a miniature model designed to latch onto Spider-Man's face and invade his mind through use of radiation and a large six-armed model stronger than any other. The miniature spider-slayer psionically connected to Spidey's mind, copied thoughts of his loved ones, and broadcasted it to other mini-slayers. Smythe gave Spider-Man the choice of either stopping the others or preventing the six-armed one from killing Jameson. Spidey eventually defeated all the spider-slayers at the same time, but Jameson knocked Smythe out with a baseball bat for threats on his family.
Smythe returned again and used a poisonous spider to send John Jameson, aka Man-Wolf, into a hospital.
Allistair appeared at the Raft as a newly made Spider-Slayer. He kidnapped Mac Gargan turning him into a cyborg Scorpion, and convinces him to join his crusade against J. J. Jameson.
Smythe has amassed a small army of cyborg minions (the Army of Insects) and attack the site of John Jameson's latest space mission, sabotaging the launch and holding John for ransom Smythe's new plan was to kill all those close to Jameson, but not to kill Jameson himself so Jameson could feel the same suffering that he did losing his father. Smythe's actions get Jameson's wife Marla killed.
During the Spider-Island storyline, J. Jonah Jameson brings Alistair Smythe from Ryker's Island to demand his help in resolving the spider-flu plague transforming ordinary citizens into "Homo Arachnis". Alistair Smythe laughed at the irony of how Jameson has gained spider powers. At the moment, J. Jonah Jameson transforms and seriously wounds Smythe by biting a chunk out of his neck.
Despite his injuries, Smythe is seen alive and well as a prisoner in the Raft.
Powers and Abilities
Alistair wears a carapace that gave him increased strength and gave him the ability to walk again by interconnecting with his spine. Alistair had bird-like talons for feet; a long, curved blade-like weapon jutting from each shoulder; a pair of smaller, jagged blade weapons on each forearm; and a specially made web-shooter that fired from the forearm area. Alistair, like his father, is skilled in the field of Robotics and has rebuilt and created his own Spider-Slayers.