Call of Duty fans are speculating that classic titles, such as 2007's hugely popular Call of Duty 4: Modern Warfare, could soon be coming to Xbox Game Pass after suddenly appearing on the Microsoft Store for PC. When Microsoft finalized its acquisition of Activision-Blizzard back in 2023, one thing fans were hopeful to see was Call of Duty's extensive library of shooters make its way to Xbox's popular Game Pass subscription service.