Alistair Smythe was the son of famed robotic expert Spencer Smythe. He was the inventor of the Spider-Slayers, a series of robots designed to destroy Spider-Man. The initial generation of Spider-Slayers were created by Alistair's father and commissioned by J. Jonah Jameson.
The Spider Slayers
After Spencer failed to kill Spider-Man and ended up getting destroyed as a result, Alistair inherited the legacy from his father and gained a new-found hatred toward Spider-Man. He initially worked for the Kingpin but left in disagreement over how to deal with Spider-Man and went solo.
After being crippled in the last battle with Spider-Man, he sent the Spider-Slayer Mark VIII to hunt him once again and attacked Mary Jane Watson's apartment. He later found him at a construction site where he was about to defeat the web-slinger, but a construction worker saved his life. He later tracked him to Pittsburgh when he was called to help MJ. The slayer tracked him to Duquese University. Spider-Man lured the machine out of the University to protect everyone. He was about to defeat Spider-Man but MJ smashed him with her car. He tried to dose Spidey with chemicals, but MJ came to his rescue smashing his legs. This gave Spider-Man enough time to shake off the effects of the gas and defeat the Spider-Slayer. 
After being confined in an asylum, Alistair released himself and took several other inmates with him in order to construct a new series of Spider-Slayers that tracked Spider-Man across the city. His plan of revenge forced the inmates to assist in the machines' construction. After sending a series of slayers after Spider-Man, Alistair lured Spider-Man to his residence for one final battle.
In order to defeat Spider-Man on his own, Alistair enhanced himself by encasing his entire body in a biorganic carapace that not only served as a full body armor, but increased his strength and gave him the ability to walk again by interconnecting with his spine. The physical structure of the carapace gave Alistair bird-like talons for feet, a long, curved blade-like weapon jutting from each shoulder that could fire lasers, a pair of smaller jagged blade weapons on each forearm, and a specially made web-shooter that fired from the forearm area. Eventually, Spider-Man defeated Alistair and made sure he and the surviving asylum inmates were taken to custody.
During Scarlet Spider's brief stint as sole web-slinger in town, Smythe (still carapaced as the Ultimate Spider-Slayer) started a war with a new set of slayers he intended to sell on the black market. These Cyber-Slayers—which could be controlled remotely by turning one's thoughts into the slayers' actions—were probably named as such because the initial target was neither Spider-Man nor Scarlet Spider, but Lady Octopus and her crew. However, as fate would have it, the Scarlet Spider was caught in the middle and temporarily allied with the Cyber-Slayers, a fact that did not go over well with Smythe.
Smythe later met with Scorpion who wanted to use one of his "Mini-Slayers" to attack Spider-Man and his libel lawyer She-Hulk on their court date against JJ Jameson. The robots were no match for the pair and they easily destroyed the robotic assassins. To get revenge he posed as Willie Lumpkin to sneak a "Mini-Slayer" into the Baxter Building to set a trap for She-Hulk and her new husband John Jameson. He was successful and activated the unit to bite Jameson causing the transformation into the "Man-Wolf" once again.
Smythe found his way out of prison and sought revenge on both Spider-Man and J. Jonah Jameson for the death of his father. He coerced Jameson to alter the stories in the Daily Bugle or else he would kill JJJ's wife and son. Once Spider-Man discovered Smythe's trail, he followed it back to the Bugle where Smythe assaulted him with recreated versions of every Spider-Slayer ever sent after Spider-Man in the past plus a pair of new creations—a miniature model designed to latch onto Spider-Man's face and penetrate his mind through use of radiation and a larger six-armed model arguably stronger than any other created. While attached to Spider-Man's head, the miniature spider-slayer psionically connected to Spidey's mind, copied thoughts of his loved ones, and broadcasted that information to all the other Mini-Slayers. Smythe gave Spider-Man the choice of either stopping them or preventing the Six-armed Slayer from destroying Jameson. Spidey eventually shut down all the Spider-Slayers at the same time, but it was Jameson who knocked out Smythe with a baseball bat for threatening his family.
Alistair Smythe returned with a new metallic body armor and was hunting down all of J. Jonah Jameson's friends and family. Smythe infiltrated the Raft and made off with Mac Gargan. He performed a cybernetic operation on him, turning him into a cyborg Scorpion, and convinced him to join his crusade against Jameson. Smythe had amassed a small army of cyborg minions, all of whom wanted revenge on Jameson. Smythe, Scorpion, and a new villain named Fly-Girl led their army to attack the site of John Jameson's latest space mission, sabotaging the launch and holding John for ransom. Smythe's actions got Jameson's wife Dr. Marla Jameson killed. Jameson vowed to see Alistair Smythe get the death penalty.
When Smythe was going to be executed, Mayor Jameson called Spider-Man to help oversee the procedure in case he attempted to escape. During this time, Spider-Man's body was possessed by the mind of Otto Octavius.
Just as Smythe's execution started, a swarm of miniature Spider-Slayers attacked, allowing Smythe to attempt an escape. However, the swarm was counteracted by Otto's own Spider-Bots. As a failsafe, the Spider-Slayers infiltrated the prison's infirmary and enhanced Boomerang, Vulture, and Scorpion, whom Smythe subsequently enlisted to kill Spider-Man.
During the ensuing confrontation against Smythe's forces and Spider-Man, the villain shut down the power on the entire island. Once Spider-Man got the upper hand against the Spider-Slayer and impaled him with his own blade, the robotic components of his body kept his mind alive. In a last-ditch effort to survive, Smythe attempted to transfer his mind into Spider-Man's body. However, due to Octavius having already done this, he had equipped his costume with the necessary metal plating to prevent such thing. Just before Smythe died, Spider-Man taunted him, revealing his true identity as Otto Octavius.
Dead No More
The Spider-Slayer's body was buried at a potter's field cemetery reserved for notorious criminals, from where it was exhumed by the Jackal as part of a plan to use cloning technology to revive all of Spider-Man's foes and allies.
Without his armored suit, Alistaire is a normal human.
Biorganic Carapace: Smythe invented a biorganic carapace that serves as a full body armor, and increases his strength and gives him the ability to walk again by interconnecting with his spine. The physical structure of the carapace also gives Alistaire 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 fires from the forearm area.
- Enhanced Strength
- Enhanced Speed
- Enhanced Agility
- Enhanced Reflexes
- Durability: Suit seems to have fully capable of deflecting bullets and others.
- Claws and blades: Smythe has a long, curved blade-like weapon jutting from each shoulder, a pair of smaller and jagged blade weapons on each forearm. He also has some kind of claws in his hands.
- Skilled Engineer: Smythe is very skilled engineer since he has made his suit and other inventions on his own.
Skilled Combatant: Smythe seems to be very skilled combatant, for example he defeated 4 Raft guards and Mach-5 on his own.
Biorganic Carapace armor
Blades and claws in his hands
- 44 appearance(s) of Alistaire Smythe (Earth-616)
- 4 appearance(s) in handbook(s) of Alistaire Smythe (Earth-616)
- 4 minor appearance(s) of Alistaire Smythe (Earth-616)
- 11 mention(s) of Alistaire Smythe (Earth-616)
- 2 mention(s) in handbook(s) of Alistaire Smythe (Earth-616)
- 18 image(s) of Alistaire Smythe (Earth-616)
- 3 quotation(s) by or about Alistaire Smythe (Earth-616)
- 1 victim(s) killed by Alistaire Smythe (Earth-616)
- 6 item(s) used/owned by Alistaire Smythe (Earth-616)