Gwen Stacy

Gwen Stacy is the girlfriend of an alternate universe Spider-Man.

Biography
Gwen is the fiancée of wealthy industrialist Peter Parker, the superhero Spider-Man. One night Gwen finds Peter in his old costume. She tells him that the party's just about to start and he should get ready, and the old costume is a nice touch. Unbeknownst to her, her Peter is gone entirely and this Peter was completely different, and there was another threatening to destroy her dimension.

At the party Gwen notices that the Peter she sees is not her Peter. She searches around and finds the first Peter she found, and realizes that the one at the party is Spider-Carnage. She then assists Spider-Man by using a sonic gun to defeat the evil version. She is successful until her Peter's lawyer, Wilson Fisk, stops her. Spider-Carnage then grabs Gwen and swings away. Spider-Man follows but knows his symbiote powered counterpart is too strong for him.

While captured, Spider-Carnage explained that his plan was to destroy every single dimension. But since his last attempt failed he will have to do it one at a time. Spider-Man arrived and explained that Spider-Carnage wouldn't go through with it because he wouldn't. Spider-Man then revealed that he had brought along Uncle Ben, who in this universe was still alive. Uncle Ben reminded Spider-Carnage about great power and great responsibility. Spider-Carnage then tried to reject the Carnage symbiote but was unable to, so he threw himself into a dimensional portal thus destroying himself, the symbiote, and the time dilation device.

Background
In the comics, Gwen Stacy was Spider-Man's greatest love. However, when the Green Goblin learned of Spider-Man's secret identity he kidnapped Gwen and she was killed in the resulting battle. The story arc was a significant influence on Spider-Man's life, and ultimately led him to Mary Jane Watson.

However, broadcasting standards would not allow the series to portray a character dying. Despite getting around this restriction in matters such as Uncle Ben and Spider-Carnage, the producers felt they could not include a character that was destined to die. Elements of the character were still incorporated into the show. While the comics had a love triangle between Peter, Mary Jane, and Gwen the show instead included Felicia Hardy, whose comic counterpart was not quite interested in Peter. The episode Turning Point adapted The Night Gwen Stacy Died storyline into show while keeping the same emotional effect. Mary Jane would then replace Gwen again when her clone came back, instead of Gwen's clone in the comics.

It is unknown whether or not there was a counterpart to Gwen in the normal universe.

Ironically, the comic's Spider-Man would later enter an alternate universe where Gwen was still alive in the House of M storyline.