Doom is a classic first-person shooter video game released in 1993 by id Software for MS-DOS. It is considered one of the most influential video games of all time, and is credited with popularizing the first-person shooter genre. In the game, players take on the role of a space marine who must fight through hordes of monsters in order to complete various objectives. The game contains a number of puzzles for the player to solve, as well as several weapons and items to collect. It also features a multiplayer mode, allowing up to four players to compete against each other or cooperate to complete levels. Doom has since been ported to numerous platforms, including the PC, Mac, PlayStation, and Xbox. Doom is often cited as one of the most influential games of all time, and has spawned numerous sequels, spin-offs, and other related media.
Discontinued No further updates since November 2013: http://assault.cubers.net/ (like Alien Arena, also noted to be discontinued).
It's DOOM but 999999999999999999999x is better and modern (including multiplayer).
Discontinued development is not stopped, but the latest version, 0.8.8, was released in February 2012.
It is a story-driven, third-person action game, while Doom is a first-person arcade game.
Discontinued The last update was published on September 6, 2013.
Kill demons non-stop with a Halloween-like setting, similar to Doom.
Half-Life
Xonotic
Quake
Borderlands
AssaultCube
Zandronum
OpenArena
Half-Life 2
Mafia
Dead Space
Freedoom
Alien Arena
Hexen II
Painkiller
Aion
Digital Paint: Paintball 2
Uebergame
Alien Swarm
Shadow Warrior Classic Redux
Rage
It is a fast-paced FPS game with tons of enemies, beautiful environment and some role-playing elements.