Although Spider-Man and Punisher have teamed up numerous times, the pair don't always see eye to eye, and that's hardly surprising considering Frank Castle tried to murder Spidey when they first met. Talk about getting off on the wrong foot.
On that occasion, Peter's Spider Sense saved him from a Punisher bullet and the pair later joined forces to take down the Jackal, the story's big bad, but Marvel has also explored what would have happened if the assassination attempt was successful.
This scenario played out in the 1994 alternate universe title What If The Punisher Had Killed Spider-Man? This time, Frank rigged a Doctor Octopus dummy with an explosive device and blew Spidey to oblivion, only to die in the proverbial fallout.
Sometime after the wall-crawler's death, Punisher realises he took out the wrong guy and goes after the Jackal. He put a permanent end to the villain, but finishes up on the wrong side of a fatal NYPD gunshot during this act of vigilantism.
In a sense, failing to kill Spider-Man saved Frank Castle's life.