I Really, Really Hate Clones

Spider-Man is taken to an alternate dimension where due to a series of events, its native Peter has bonded with the Carnage symbiote to become the maniacal Spider-Carnage, who has devastated and demolished New York City with the aid of Kingpin, Alistair, the Hobgoblin, and the Green Goblin. The Beyonder tells Spider-Man that his deranged counterpart plans to use a matter-disintegrator bomb powered by the Time-Dilation Accelerator to destroy the entire multiverse, and the only way to stop him is for Spider-Man to lead a group of Spider-Men from different dimensions to prevent the blast. Unfortunately, one of the Spider-Men is suffering from the six-armed mutation and turns into the Man-Spider mid-mission.