Fans know that Spider-Man has a strict no-killing policy. From his very first appearance in Amazing Fantasy #15, Peter Parker has always chosen to web up his enemies rather thank ill them (including the burglar who killed his Uncle Ben). But not every version of Spider-Man is as strict.

Films like Sam Raimi’s Spider-Man or Marc Webb’s The Amazing Spider-Man may have entertained a more vengeful Spider-Man who wanted a more gruesome end to the burglar, but most fans accept that Spidey is strongly opposed to lethal force. But in one alternate universe readers got to see that, with proper training, Spider-Man’s precognitive Spider-Sense could make him one of the deadliest assassins in the Marvel Universe.

Related: Spider-Man Never Realized His Best Spider-Sense ATTACK

The story, which took place in What If? Spider-Man vs. Wolverine, offers an alternate ending to the one-shot Spider-Man vs. Wolverine and shows just how deadly Spider-Man’s powers make him. Or would, if he decided to start killing.

Spider-Man vs. Wolverine: The Original Kill

Wolverine and Spider-Man Team-Up Comic

In the mainstream universe, Peter Parker traveled to with Daily Bugle reporter Ned Leeds to investigate the killing of Russian spies in the U.S. by Charlemagne, a freelance operative. Once in Berlin, Peter runs into the X-Men’s Wolverine, who discovers Peter’s secret and tells him to leave. Before Peter can warn Ned, however, Leeds is killed by a group of assassins.

Deciding he needs to avenge his friend’s death, Peter gets a knock off Spider-Man costume and discovers Charlemagne and Wolverine are friends and lovers. He also learns Charlemagne is being targeted for assassination by intelligence agencies around the world after she killed her Russian bosses. Spider-Man and Wolverine take down Charlemagne’s assassins, but Charlemagne, knowing it’s only a matter of time before she gets caught, asks Wolverine to kill her quickly. This leads Spider-Man to fight Wolverine to keep the mutant from murdering the woman. The fight ends tragically when Spider-Man accidentally punches Charlemagne fatally in the face. While Peter is horrified by what he did, he eventually returns to New York and processes his guilt with Mary Jane’s help.

The Spider-Man Who Became an Assassin

Spider-Man Assassin Fighting Black Widow

However, What If? Spider-Man vs. Wolverine reveals an alternate Marvel universe where Wolverine convinces Peter to stay in to save Charlemagne’s sister – another operative named Alex. Believing this can make up for killing Charlemagne, Peter agrees – and discovers Alex bears a strong resemblance to Gwen Stacy. This, along with his obsessive need to keep Alex alive from further attacks by the Russians, makes Peter stay even longer in .

Peter begins training with Nebo, the same man who taught Alex to become a contract killer. In addition to teaching Spider-Man combat skills, Nebo hones Peter’s Spider-Sense. While the danger sense used the only trigger when Spider-Man was attacked, Nebo notes that as the sense expanded, Peter could sense when Nebo was thinking of attacking him. Eventually, Peter’s expertise with his Spider-Sense grew so strong that he could tell an attack was coming before the attacker even considered threatening him. Peter can even tell every detail of an attack – from the order of the moves, to the number of attackers, to the exact words each opponent will use – thanks to his weaponized Spider-Sense.

Unfortunately, these deadly skills lead Spider-Man to take ops work along with Wolverine and Alex. While he tries to cling to his sense of morality, eventually he discards it completely – even modifying his web shooters so they fire bullets as well as webbing. He gets romantically involved with Alex and finally realizes that he’s changed too much to go back to being a “friendly neighborhood Spider-Man.” The story ends with Peter, now a cold-blooded killer, still in Europe accepting assassination jobs.

Spider-Man Kills Enemy Bullet Shooter

This Peter Parker (identified as the Spider-Man of Earth-8351) later appears in the Spider-Verse storyline. Recruited by the Superior Spider-Man (actually Doctor Octopus controlling the mainstream Peter Parker’s body), Spider-Man s the team of alternate Spider-People. However, his killer spider instinct fails him when he’s killed by one of the Spider-Totem hunting Inheritors.

Considering how deadly this Spider-Man’s more trained Spider-Sensee made him, it seems strange that he was killed so quickly in the Spider-Verse story. Later Spider-Verse stories establish that the Spider-Sense of all Spider-Men in the multiverse is an “arachnofrequency” tied to the Web of Life and Destiny (a construct that binds together all of time and space). These “arachnofrequencies” give alternate Spider-Men an instinctive awareness of the world around them and what will happen. However, during Spider-Verse, the Inheritors disrupted the Web of Life and Destiny, affecting every “Spider-Totem’s” Spider-Sense. Thus, the assassin Spider-Man’s powers were not at their peak.

Given this, it’s actually scary how dangerous a trained Spider-Sense can make Spider-Man. Many superheroes seem content to write Peter Parker off as an immature, local superhero, but alternate stories show just how deadly Spider-Man’s powers can make him.

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