They said it all started with a flash in the sky and a ripple through the clouds. Nobody knows what caused this exactly, but some people think it might be a punch. Was he really that strong? Had the infection made him so determined to get here in search of a brand new food supply? At the time I said no… but having experienced this hunger firsthand I’m afraid that I now know better. The Avengers were the first on the scene. Can you picture them? Faces grave, concerned for all those human casualties. That idiot Colonel America reassuring everyone that everything would be fine now that the super heroes have arrived. What they didn’t know is that the infection had targeted the super heroes of this dimension and a thousand realities before us. This was how it consumed, you see… by infecting super heroes just like him and sending them out to infect the others. Within twenty-four hours, we’d consumed the entire planet. One super hero from an infected universe… That was all it took to end an entire world.
When the zombie Sentry arrived, the Avengers were sent to investigate. They were quickly infected and spread the virus to the other heroes. In less than 24 hours, all of Earth was infected. Despite the efforts of Nick Fury and Ashley Williams, nothing stopped the zombies from eating and spreading the disease to the whole world. The main reason for why the infection spread so quickly could be considered the zombified Quicksilver, since he used his speed to travel around infecting other countries.