Games similar to Natural Selection include Doom. It's paid, but Tremulous and Unvanquished are free. Other options are Shadow Warrior (Reboot), Prodeus, Dead Space and DUSK. You can choose from more than 10 First-Person Shooters like Natural Selection for Windows, Mac and Linux.
Doom is a science fiction horror-themed first-person shooter video game in which players assume the role of a space marine, popularly known as "Doomguy", who must fight his way through the hordes of invading demons from Hell.
United States
Shadow Warrior is a series of first-person shooter video games that focuses on the exploits of Lo Wang, a modern ninja warrior who fights through hordes of demons.
Poland
EU
Prodeus is a first-person shooter of old, re-imagined using modern rendering techniques and technology. Experience the quality you’d expect from a modern AAA game, designed with retro aesthetics and gameplay that invoke the tech-imposed limits of older hardware.
Canada
Dead Space is a survival horror third-person shooter video game for Microsoft Windows, PlayStation 3 and Xbox 360.
United States
Tremulous is a free, open source game that blends a team based FPS with elements of an RTS. Players can choose from 2 unique races, aliens and humans. Players on both teams are able to build working structures in-game like an RTS.
United States
Unvanquished is a free, open-source first-person shooter combining real-time strategy elements with a futuristic, sci-fi setting. It is available for Windows, Linux, and Mac OS X.
Battle through an onslaught of mystical backwater cultists, possessed militants & even darker forces as you attempt to discover just what lurks beneath the Earth in this retro FPS inspired by the '90s legends.
United States
Zandronum is a multiplayer oriented port, based off Skulltag, for Doom and Doom II by id Software.
Aliens vs. Predator is a science fiction first-person shooter video game, developed by Rebellion Developments
Japan
Wrack: Exoverse is the follow-up to the 2014 first-person shooter Wrack. It was a very fast-paced, arcade-style game with heavy influences from classic shooters like Doom and Quake.
United States
