Despite the fact that they’ve fought against each other in the comics and the MCU movies, Spider-Man and Thanos have rarely shared much screen time. In Avengers: Infinity War, Spidey got to kick Thanos a few times and then helped Iron Man (unsuccessfully) remove his gauntlet. In the original Infinity Gauntlet comic saga, Spider-Man got to hit Thanos in the face with a web and kick him in the face, but was subsequently killed by Thanos’ artificially created girlfriend (don’t worry, he got better).
However, Thanos and Spider-Man got to interact much more in Spider-Man #17, which saw Peter Parker get killed (again) and meet both Thanos and Mistress Death as he passed into the afterlife. In a shocking twist, however, Peter ended up convincing Mistress Death to let him live!
The unexpected meeting happened after Spider-Man, while delivering some barbeque sauce to Aunt May, sees some window washers falling as their platform breaks. Spidey manages to save the men, but the platform falls onto a cooling machine full of explosive freon gas. Seeing a mother and her child in the path of the explosion, Spider-Man throws himself at them and uses his own body to shield them. However, he dies in the attempt and his spirit is thrown out of his body.
Satisfied that he at least managed to get the mother out of harm’s way, Peter lets himself float away and finds himself in a beautiful white light. Wondering if he’ll be reunited with Gwen Stacy or his mother, he follows the light, but ends up in a weird junkyard full of different religious and spiritual items. And he has company – for Thanos and Mistress Death are both in this stage of the afterlife waiting for him.
Taunting him for his futile attempt at being a hero, Thanos gets Spider-Man to take one last look at his body and the life he left behind. As he does, however, Peter sees that his last rescue wasn’t as successful as he thought. While he managed to save the woman from the freon gas explosion, her little girl died and is also drifting in the half way point between life and death. Suddenly full of new resolve, Spider-Man demands that Thanos and Death release the girl and let her return to her mother.
Thanos simply tells Spider-Man that such a thing is never done, causing Peter to start hammering away at the Mad Titan, hoping this will make a difference. Instead, Thanos strikes him down and tries attacking him emotionally, telling him that all he’s accomplished as a hero is to inspire greater villainy. He then grows to enormous size, trying to intimidate Spider-Man, but Peter just points out that Thanos is just trying to make him feel small in a realm where even Thanos admits physical things don’t matter.
All this while, Death has been silently observing the fight seemingly impassive. Suddenly, however, she stares at Thanos as if he’s missed something. Unnerved, Thanos asks if Death wants Spider-Man. When she doesn’t respond, Spider-Man speaks up, acknowledging that it might be arrogant for him to request that she give up two lives, but pointing out that he fights not for his own life but for the life of the girl. Although Death doesn’t respond, in the next instant, both Spider-Man and the girl return to life, with Spidey retaining only vague memories of his time in the afterlife.
An almost forgotten one-shot, Spider-Man’s brief time being dead offers a unique look at Mistress Death, one that frankly, should unsettle Thanos. For most of his existence, Thanos has pined after Death and even acquired the Infinity Stones to wipe out half the population of the universe and correct what he believes Death sees as a “great imbalance.” But if someone like Spider-Man can convince Death to resurrect not only himself but a seemingly insignificant child, then it’s possible that Thanos is misreading some of Death’s desires, further frustrating him and giving him a personal vendetta against Spider-Man.