2. Call of Duty 2
Year of Release: 2005
The Call of Duty franchise epitomizes everything a modern first-person shooter ought to be: A game with a compelling, story-driven single-player campaign along with a multiplayer mode that can steal hours of your life. The newer incarnations are more complex and prettier, of course. But they owe a great debt to Call of Duty 2, which in 2005 took what made the original title great and doubled down. Grand cinematic sequences gave players a sense of scope, while the realism—fallen soldiers would sometimes try fruitlessly to crawl to safety—drove home the horrors of war. Iron sights on the guns, meanwhile, made this a favorite of hyper-accurate PC gamers.
Year of Release: 1993
Doom was not the first first-person shooter, but it was the most influential game in that particular genre. In fact, many consider it to be the basis for all modern FPSs, as the environments, atmosphere, and game mechanics were merely honed over many years rather than abandoned altogether.
Doom changed gaming forever. Without Doom there would be no Call of Duty series, and that is, whether you like it or not, one of the most popular franchises of all time. The Doom series still has fans today, which is an amazing achievement for such an aged game.