Spider-Carnage

Spider-Carnage is a Villain and alter ego of Ben Reilly in the comics and the alter ego an alternate Peter Parker in Spider-Man the Animated Series.

Comics
During the "Web of Carnage" arc Ben Reilly is bonded with the Carnage symbiote when it escapes from Ravencroft Institute, where its psychopathic host, Cletus Kasady, is being held, through the asylum's water pipes. Reilly struggles for control of himself, and tries to prevent the symbiote from taking over, the subsequent inner battle with the creature ends when he has John Jameson take him to a cell designed to hold Carnage, willingly subjects himself to a potentially fatal dose of microwave radiation to try to kill the symbiote, which returns to Kasady via the pipes. Seward Trainer disappears while Ben fights with the Carnage symbiote. Reilly's bank account is frozen and his possessions stolen while the Grind is burned down and Reilly is framed for arson.

Spider-Man the Animated Series
Peter Parker's life was tough, and both his Uncle Ben and Aunt May passed away. Miles Warren successfully cloned Spider-Man. One of the two versions of Spider-Man took on a new identity, changing his features, his name to Ben Reilly, and becoming the Scarlet Spider. The other hated his double for this, and sought to destroy him, bonding with the Carnage symbiote creating the creature known as Spider-Carnage.

Spider-Carnage devastated New York City, and intended to destroy all of reality. However, Ben Reilly was chosen along with various other Spider-Men from different realities to stop him.

When Spider-Carnage's plan appeared to be foiled, he simply travelled to another dimension to finish his plan there. It was the reality of the Armored Spider-Man. He worked together with the Kingpin of that world by telling him that the device will hypnotise people into obeying them. He pretended to be the Peter Parker of that world to escape suspicion, he was attacked by one of the Spider-Men and kidnapped Gwen Stacy in order to escape, threatening everyone present that if one of them follows him, he'd kill Gwen first before he destroys all reality.

Spider-Man then understood that Spider-Carnage was not truly evil, simply confused because in his reality, his Uncle Ben and Aunt May had died. Thus, Spider-Man went to the Uncle Ben who was alive in this reality. Spider-Man and Uncle Ben arrived and Ben reformed Spider-Carnage by reminding him of the Peter Parker inside him. Spider-Carnage prevented the destruction of all reality but could not successfully remove the Carnage symbiote, jumping into an unbalanced portal, vaporizing both himself and the symbiote.