When was first revealed in a trailer showing Peter and Miles fighting side by side, there was speculation that the game could have an additional co-op mode for players to take control of both heroes simultaneously. As the game's promotion went on, however, it became clear that Insomniac Games' sequel would be single player just like its predecessors.
[Warning: The following article contains spoilers for Marvel’s Spider-Man 2]
does allow players to take control of multiple characters though, with Peter and Miles being co-leads, and a GTA-esque character-swapping mechanic allowing for instant switching between the two when in the game's open world. Mary Jane is also playable in the sequel after her divisive stealth sections in, albeit far more capable than before due to spending more time in the field and training with Silver Sable — and returning with one of her non-lethal pistols — while reporting in Symkaria.
Although followed both Peter and Miles' heroic journeys and seemed like an obvious way to incorporate multiplayer, this likely wouldn't have worked very well during its main campaign. Insomniac's games have been extremely story-driven, and while co-op titles such as have shown co-op titles can be just as narrative driven as single player ones, there are so many fixed plot points in that one player would likely have felt short-changed as a result.
The biggest example of this would be the fight between a symbiote-enhanced Peter Parker and Miles Morales toward the end of the game's second act. A huge part of the game's story is Peter becoming corrupted by the Venom symbiote, and how it changes his relationships with those around him. Peter realizing what the suit is doing to him and removing it is a crucial plot
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