10 Unbelievable Retcons That Made Comics Worse
5. Gwen Stacy Slept With Norman Osborn Before Her Death - Spider-Man
The Night Gwen Stacy Died was a seminal moment in Spider-Man's history, and so anything that would dare mess with the arc was always going to be divisive. Unfortunately said 'thing' came during J. Michael Straczynski's stint on Spider-Man, a run that blew hot and cold over its several years on the stands.
Sins Past was the arc in question, and it revolved around Spidey being attacked by two unnamed assassins who blamed him for the death of Gwen Stacy. Peter eventually discovers, thanks to MJ, that Gwen had slept with Norman Osborn prior to her death and had become pregnant as a result. She then gave birth to twins and threatened to expose Osborn publicly, which was apparently the motive he needed to murder her in Gerry Conway and John Romita's iconic story.
Needless to say, the story has gone down as one of Spidey's lowest moments of the modern era. Mary Jane withheld the information from Peter for years and the idea of Gwen's secret goblin offspring coming back to haunt Pete didn't make much sense either.