WARNING: The following article contains spoilers for Marvel 2-In-One #7 by Chip Zdarsky and Rámon K. Pérez, in stores now.
In Marvel 2-In-One, Johnny Storm, Ben Grimm, Doctor Doom and Rachna Koul have been taking a tour of the Marvel Multiverse with the help of the Multisect, a device created by Reed Richards that enables inter-dimensional travel. While the main goal as far as Johnny is concerned is to try and find the rest of the Fantastic Four to reunite the team and prevent the Thing and the Human Torch's powers from fading out completely, Ben continues to operate under the assumption his family is dead. For him , the trip is merely a way to keep Johnny's hopes up as his powers wane.
Unbeknownst to the rest of the group, Dr. Koul is actually leading them across parallel realities under false pretenses. They began their journey by visiting a universe where Earth was the final planet left alive in the cosmos, followed by a world where another Doom had murdered the Fantastic Four.
In issue #7, we visit yet another grim alternate reality, an Earth that has been turned into a Mad Max-like world, with barren wastelands and the strong ruling over the weak, demonstrating their power by holding cruel death matches between man and monster. But the real surprise of this alternate reality comes in the identity of the one who rules over all: Peter Parker, aka Spider-Man.
The Spider-Man we meet here is a far cry from the one we all know and love. He's cruel and evil, and he appears to be completely unhinged, his usual wackiness taken to unsettling extremes. But what's even more troubling is his appearance: yes, he's still wearing his Spider-Man costume, but he doesn't have his usual mask. Instead, he's wearing Captain America's mask, with the signature Spidey eyes added to it. Then, to complete the look, he's got a furred caped which seems to be have been "borrowed" from (a presumably dead) Kraven the Hunter.
As Doctor Doom and the rest of his fantastic group discover more about this reality, we learn exactly how Peter Parker became a crazed and ruthless warlord who rules over the people of Earth. In this universe, the superhero civil war between Captain America and Iron Man was elevated to extremes, eventually turning into a full-on global conflict. To put an end to it, a hopeless Spider-Man killed Tony Stark, and imprisoned Captain America, acts which effectively made the kind-hearted superhero snap. Not only is this Spider-Man evil, he truly appears to have gone off the deep end. This is evidenced by the fact that he actually actually talks to the Captain America mask on his head, addressing it like it was the real Steve Rogers.
This world paints a much different, and quite gruesome, end to the superhero civil war. In the original event, Spider-Man was effectively the one caught in-between both camps. The fact that in this reality he was the one who put a stop to the conflict by killing one hero and imprisoning another speaks to the severity of the war, and of the cost of putting a stop to it. All it took was the sanity of the world's greatest superhero.