WC: First-person shooters have been a staple of the gaming industry since id Software first popularized it with the likes of Doom and Wolfenstein. Over the years, there have been some truly genre defining games such as the Halo and Call of Duty franchises.
The games themselves emerge you in the world of the character you control. seeing everything through their eyes. The weapons as well have helped the genre to become a staple, with the devastation of the shotgun at close range to the lethal sniper if you prefer to pick your targets off at a distance, and when your ammo is all gone, you can always rely on your trusty knife or go toe to toe with your enemies and beat them to a pulp with your bare fists.
Here we count down the 20 greatest first-person shooter levels of all-time from a whole variety of genres.