6. Halo: Combat Evolved
Oh Halo, how do we love thee? Let us count the ways. You started so many brilliant shooter trends that still thrive today. A trigger for fast grenade tossing, powerful melee attacks that encourage clever footwork and brutal aggression, the original Halo was the most important console shooter since GoldenEye on the N64, proving that two sticks and two triggers could rival the mouse and keyboard for fluid FPS control.
It also had a campaign of magnificent pacing, free from the busy work and keycard hunting of other shooters. Halo knew that what you wanted to do was shoot, shoot, and shoot some more. It also forced you make to make decisions about weapons to carry, limiting your arsenal to two guns, and letting you switch between them quickly for advanced tactics. Best of all, with the game's recent HD-remake, you can play the game without putting on your nostalgia goggles.