Can you imagine playing Modern Warfare 2 and suddenly an alien invasion happens and after you count the dead, they start rise from their grave? Sure it sounds ridiculous, but when Infinity Ward was first writing the script for the sixth installment of Call of Duty — stuff like this was considered. Thankfully it never made it in the final product, but one of the writers discussed the idea of a possible sci-fi COD.

“In the beginning we talked about having things in Modern Warfare 2 like outbreaks, viruses, chemical warfare, and even outlandish things such as aliens and the living dead,” says Jesse Stern. ” We worked our way through it before we finally ended up with a more grounded version of the real world as it’s depicted in Call of Duty: Modern Warfare 2. And as we were kicking around scenarios for conflict, we kept stumbling into things that were happening in real life, which was honestly unintentional.”

This might sound far-fetch, but if you remember some rumors that started to emerge back in 2008, it starts to make sense. Sites were reporting that Infinity Ward was actually making an unnamed sci-fi title. The news supposedly came from an insider from the studio. “We are currently working on a new sci-fi title, we cannot release any more information as of yet, we may or may not announce it at E3,” said the anonymous source. Of course E3 came and went, and nothing was ever mentioned. One and a half years later, Infinity Ward released one of the most successful games of all time — and didn’t include zombies.