Free Sci-Fi online FPS games

This second list includes free online first-person shooters that are unrealistic and usually set in the future. These FPS's often have similarities to shooters like Quake or Unreal Tournament. Most of them have relatively fast-paced gameplay and fictional weaponry like gravity guns and plasma weapons. There are around 10 games in this list that also have Linux and/or Mac versions. Some shooters may have very low player base or no players at all.

Team Fortress 2

Team Fortress 2 is a team-based multiplayer first-person shooter that recently became a free-to-play game. This shooter has cartoon style graphics and nine different player classes.

System requirements: 1.7 GHz CPU, 512MB RAM, DirectX 8.1 level graphics card.

http://www.tf2.com/  (also available for Mac)

Quake Live

Quake Live is a browser-based variant of famous online first-person shooter, Quake III Arena. Some arenas, game types and server options are not available for free users.

System requirements: 800 MHz CPU, 512MB RAM, NVIDIA GeForce4 MX / ATI Radeon 8500.
http://www.quakelive.com/  (also available for Linux and Mac)

Half-Life 2: Deathmatch

Half-Life 2: DM is a fast multiplayer first-person shooter where you can also throw objects with gravity gun. Half-Life 2: Deathmatch is only free for ATI and NVIDIA graphics card users.

System requirements: 1.2 GHz processor, 256MB RAM, DirectX 7 level graphics card.
ATI , NVIDIA 

F.E.A.R. Combat

F.E.A.R. Combat is a free stand-alone multiplayer component of F.E.A.R., the horror themed first-person shooter. You have to register a free CD-Key to join F.E.A.R. Combat.

System requirements: 1.7 GHz Pentium 4, 512MB RAM, 64MB GeForce 4 Ti / Radeon 9000.
http://projectorigin.warnerbros.com/fearcombat/

Genesis AD

Genesis AD is a free-to-play 3D Sci-Fi themed MMOFPS published by ijji. Genesis AD is set three hundred years in the future and it features fast-paced gameplay and wall jumping. 

System requirements: P4 2.4GHZ, 512MB RAM, Geforce 6600.
http://genesis.ijji.com/ 

Wolfteam

Wolfteam is a fast-paced MMOFPS with many special features - like ability to transform into a werewolf. Wolfteam has large assortment of modern weaponry and 7 game modes.

System requirements: 1.4 GHz Pentium 4, 512MB RAM, GeForce 5700 or higher.
http://wolfteam.softnyx.net/ , http://wolfteam.aeriagames.com/

Xonotic

Xonotic is a free open source fast-paced first-person shooter that is direct successor of the Nexuiz Project. Xonotic features new physics, maps, player models and animations.

System requirements: unknown, similar to Nexuiz.
http://www.xonotic.org/  (also available for Linux and Mac)

Mars War

Mars War is a free-to-play Sci-Fi MMOFPS with huge maps that can contain hundreds of real players. Mars War has wide variety of robots, equipments and vehicles (tanks, spaceships).

System requirements: Pentium IV 2.0 GHz, 1GB RAM, Geforce 6200 / Radeon 9550.
http://marswar.mmolover.com/

Nexuiz

Nexuiz is a free fast-paced cross platform first-person shooter, which runs on DarkPlaces engine. Nexuiz also includes a relatively short single-player campaign with bots.

System requirements: 1 GHz Pentium III or AMD Athlon, 512MB RAM, GeForce 2.
http://www.nexuiz.com/classic.php  (also available for Linux and Mac)

Warsow

Warsow is a multiplayer free FPS set in a cartoonish world. Warsow's gameplay focuses on fast movements and tricksjumps (such as bunny hopping, wall jumping, rocket jumping...).

http://www.warsow.net/  (also available for Linux and Mac)

Alien Arena 2011

Alien Arena is a retro Sci-Fi multiplayer FPS based on the CRX engine. Alien Arena 2011 has wide set of fun and unique weapons, dozens of maps, various play types and accessories.

System requirements: 1GHz CPU, 256MB RAM, OpenGL compatible graphics card.
http://red.planetarena.org/  (also available for Linux and Mac)

Celestial Impact

Celestial Impact is a team based multiplayer first-person shooter that takes place on asteroids floating in space. It features destructible world and ability to add terrain to the landscape.

System requirements: 2 GHz CPU, 512MB RAM, 128MB GeForce 6000 series or equivalent.
http://www.celestialimpact.com/

World of Padman

World of Padman is a cartoony free FPS game set in the miniature world of Padman. WoP has over 23 richly detailed maps, each supporting up to seven different play modes.

System requirements: 1 GHz CPU, 512MB RAM, 128MB OpenGL Video Card.
http://www.worldofpadman.com/  (also available for Linux and Mac)

Sauerbraten

Sauerbraten is a free first-person shooter similar to Quake. Sauerbraten features both single-player and multiplayer modes, it also includes a dynamic ingame level editor.

System requirements: 733 MHz CPU, 128MB RAM, 32MB GeForce 2 MX.
http://www.sauerbraten.org/  (also available for Linux and Mac)

Tremulous

Tremulous is a free game that blends team-based FPS with real-time strategy elements. This shooter features two teams: humans and aliens, both teams can build in-game structures.

System requirements: 800 MHz CPU, 256MB RAM, NVIDIA GeForce 4 / ATI Radeon 9200.
http://www.tremulous.net/  (also available for Linux and Mac)

OpenArena

OpenArena is a free open-source clone of Quake III Arena. The gameplay is basically identical to the shooter it's based on, even some Quake 3 mods work with OpenArena.

System requirements: Pentium II 233 MHz, 64MB RAM, 16MB OpenGL video card.
http://openarena.ws/  (also available for Linux and Mac)

UberStrike

UberStrike is a free-to-play cross-platform online first-person shooter, available for both Mac and Windows PC. UberStrike is the world’s first browser-based MMOFPS.

http://uberstrike.cmune.com/  (also available for Mac)

Red Alert: A Path Beyond

Red Alert: A Path Beyond is a first-person shooter based on classic real time strategy, Command & Conquer: Red Alert. This shooter is standalone and free to play.

System requirements: 800 MHz CPU, 128MB RAM, 32MB DirectX 7 compatible video card.
http://www.apathbeyond.com/

Legions: Overdrive

Legions: Overdrive is a free Sci-Fi FPS based on cancelled project, Fallen Empire: Legions. Many gameplay elements in Legions: Overdrive are borrowed from the Tribes series.

System requirements: 2.2 GHz Pentium 4, 512MB RAM, NVIDIA GeForce 6800 / 8400.
http://www.legionsoverdrive.com/

SCUD Storm

SCUD Storm is a freeware game that turns Command and Conquer: Generals - Zero Hour into a 3D first-person shooter. SCUD Storm is standalone, you don't need any game to play this.

http://www.moddb.com/games/scud-storm

Starsiege: Tribes

Starsiege: Tribes is a multiplayer Sci-Fi first-person shooter with no single-player campaign. It was released for free to promote the release of Tribes: Vengeance, the upcoming sequel.

System requirements: Pentium 166 MHz, 32MB RAM, 3D graphics accelerator.
http://www.planettribes.com/

Tribes 2

Tribes 2 is a sequel to Starsiege: Tribes, set in the year 3941. Tribes 2 is a completely free to download multiplayer first/third-person shooter that takes place in fictional Earthsiege universe.

System requirements: Pentium II 500 MHz, 64MB RAM, 12MB video card.
http://www.tribesnext.com/ 

Legends

Legends is a fast-paced freeware online first-person shooter with jetpacks, similar to Tribes. This shooter also has mission editor and terrain generator integrated into the game engine.

http://legendsthegame.net/  (also available for Linux)

Galacticwar

Galacticwar is a free Sci-Fi first-person shooter that features both single-player and multiplayer modes. Galacticwar (GCW) will have single-player campaign and vehicles in the future.

http://www.moddb.com/games/galacticwar

Daikatana Deathmatch

Daikatana Deathmatch is a free and non-profit fan made multiplayer modification of Daikatana. This modification is multiplayer only and have all single-player maps removed.

Minimum requirements: Pentium 233, 32MB RAM, 4MB OpenGL compliant video card.
http://www.daikatananews.net/

Transfusion

Transfusion is a free to download online first-person shooter that aims to be a total remake of Monolith's Blood. This multiplayer only shooter is based on the DarkPlaces engine.

http://www.transfusion-game.com/  (also available for Linux)

Control Monger

Control Monger is a free Sci-Fi first-person shooter in which you take control of a robot. Control Monger features seven player types and support for LAN play.

System requirements: 1.5 GHz CPU, 256MB RAM, 3D capable card 64MB video card.
http://www.controlmonger.com/

Cube

Other free shooters

The third list contains all free shooters that aren't online FPS games. Such as single-player FPS's with no multiplayer, third-person shooters and 2D shooters. Some are just short tech demos that show capabilities of a game engine or piece of hardware. There are lots of single-player indie FPS games, also couple single-player shooters with storyline, which were made free years after release.

 Multiplayer:

 Battlefield Heroes

Battlefield Heroes is a free cartoon-style third-person shooter set in World War II, developed by Electronic Arts. Battlefield Heroes has many ingame vehicles, including tanks and aircrafts.

System requirements: 1.0 GHz CPU, 512MB RAM, 64MB video card with Pixel Shader 2.0.
http://www.battlefieldheroes.com/

Alien Swarm

Alien Swarm is a free top-down perspective co-op alien shooter released free by Valve. This action shooter features 4 classes, also dozens of different weapons and achievements.

System requirements: Pentium 4 3.0 GHz, 1GB RAM, ATI X800 / NVidia 6600.
http://www.alienswarm.com/

CrimeCraft

CrimeCraft is a third-person shooter that blends an action-packed shooter with role-playing elements. CrimeCraft is set in the near future where gangs have replaced governments.

System requirements: 1.6 GHz Intel single core, 1024MB RAM, GeForce 7600 / ATI X1600.
http://www.crimecraft.com/

GunZ The Duel

GunZ The Duel is a free online third-person shooter where you can also use melee weapons like swords and daggers. GunZ has microtransaction system for buying premium items.

System requirements: Pentium III 500 MHz, 256MB RAM, Direct3D 9.0 video card.
http://gunz.ijji.com/ 

S4 League

S4 League is a free-to-play multiplayer online third-person perspective shooter with cartoon characters. This fast-paced anime shooter has strategical gameplay and 6 game modes. 

System requirements: Pentium III 1 GHz, 256MB RAM, NVIDIA GeForce 4MX.
http://s4.en.alaplaya.net/

Battleswarm: Field of Honor

Battleswarm: Field of Honor is a blend of FPS and real-time strategy. Humans in this free game are played in FPS or TPS mode, bugs are commanded by real time strategist.

System requirements: 2.2 GHz processor, 1024MB RAM, 64MB DirectX 7 level video card.
http://www.battleswarm.net/

Soldat

Soldat is a free, unique side-view multiplayer shooting game that has fast action gameplay with lots of blood. Soldat is mix of Liero, Worms, Quake and Counter-Strike.

System requirements: 333 MHz CPU, 32MB RAM, DirectX 8.1 graphics card.
http://www.soldat.pl/

Counter-Strike 2D

Counter-Strike 2D is a free 2D clone of the famous multiplayer shooter: Counter-Strike. There are also four new modes: Deathmatch, Team Deathmatch, Construction and Zombies.

System requirements: 500 MHz CPU, 64MB RAM, 16MB DirectX 7+ 3D video card. 
http://www.cs2d.com/  (also available for Linux and Mac)

Single-player:

S.T.A.L.K.E.R. build 1935

S.T.A.L.K.E.R. build 1935 is a free to download build of S.T.A.L.K.E.R.: Shadow of Chernobyl. Build 1935 contains many features that didn't make it into the final release, also many bugs.

System requirements: 1.4 GHz CPU, 512MB RAM, 64MB GeForce 3.
Download & guide

Interstellar Marines 

Interstellar Marines is an in-development browser based, high quality first-person shooter. This single-player shooter set in a realistic and unpredictable future.

System requirements: Intel Core 2 Duo 2.2 GHz, 2GB RAM, GeForce 8800 GTS 640MB.
http://www.interstellarmarines.com/

PRISM: Guard Shield

PRISM: Guard Shield is a first-person shooter with a blend of stealth operations and fast gameplay. PRISM: Guard Shield is created by the Army National Guard and Rival Interactive.

System requirements: 1.5 GHz Athlon 64, 256MB RAM, Geforce 4 / ATI 9600 64MB.
http://www.prismthegame.com/

Area 51

Area 51 is a single-player Sci-Fi first-person shooter released as freeware by the US Air Force. It features over 15 types of weapons/equipment and a campaign with 8 levels.

System requirements: Pentium III 1.4 GHz, 256MB RAM, 64MB ATI 9500 / GeForce 3. 
Download

Euthanasia

Euthanasia is a first-person horror shooter with lots of riddles and puzzles in ten fully playable levels. Euthanasia features disturbing athmosphere and lots of horrorsequences.

http://www.moddb.com/games/euthanasia

Noah's Jungle

Noah's Jungle is an unique FPS where you explore jungle forest and capture wild animals. You play as an insane scientist who is ‘saving’ the animals of the jungle.

http://www.noahsjungle.com/

The Suffering

The Suffering is a free, but ad-supported horror themed third/first-person shooter. The player in this shooter is set in maximum-security prison, after earthquake had released the monsters.

System requirements: Pentium III 1.0 GHz, 128MB RAM, 32MB DirectX video card. 
Download

Hidden & Dangerous Deluxe

This action shooter was made free to promote the release of Hidden & Dangerous 2. Deluxe release also includes Devil's Bridge expansion pack, patches, and the level editor.  

System requirements: Pentium 166 MMX, 16MB RAM, 2MB VRAM. 
Download

Derelict

Derelict is freeware tactical first-person shooter with a Sci-Fi survival horror theme. The player in this shooter has to guide his squad of 4 marines, through increasingly dangerous levels. 

http://earok.net/derelict

Lego Wolf3D

Lego Wolf3D is a fan-made first-person shooter that combines Lego and Wolfenstein 3D using the C4 game engine. This free single-player FPS is currently in beta.

System requirements: GeForce FX 5200 / ATI Radeon 9500 / Intel GMA X3000 or higher.
http://www.drdanick.com/legowolf3d/

theHunter

theHunter is a very realistic hunting game set in open world island. Free version features only one huntable animal (mule deer), paid members can hunt all other animals.

System requirements: Pentium 4 3 GHz, 1GB RAM, 256MB Shader Model 3.0 video card. 
http://www.thehunter.com/

WHITE: The Game

WHITE is the first first-person shooter based on both the player's violence and creativity. You can create unique artwork by killing creatures that are filled with paint. 

http://www.white-the-game.com/

The Hunted

The Hunted is a standalone single-player FPS based on the Darkplaces engine. The Hunted is about a lone survivor escaping from a city that has overcome by the infected.

http://the-hunted.com/

The Hunted Chronicle 2

The Hunted Chronicle 2 is a single-player survival horror first-person shooter based off of the Darkplaces engine. The Hunted Chronicle 2 is sequel to The Hunted.

http://the-hunted.com/

Glitch

Glitch is a free to download first-person shooter that is set in a unique 3D environment in which all of the entities are constructed from particles.

https://www.digipen.edu/?id=1170&proj=1470

Terror Attack: Project Fateh

Terror Attack: Project Fateh is a 3D first-person shooter based on the 26/11 Mumbai terror attack. Terror Attack is developed by Shivam Sai Gupta, a 14 year old teen living in India.

System requirements: Intel Core 2 Duo 2.0 GHz, 1GB RAM, 512MB DirectX9 video Card. http://www.projectfateh.com/

Lone Wolf 3

Lone Wolf 3 is a freeware first-person 3D shooter which doesn't need installation. This one man project features 5 realtime generated worlds and 13 nicely animated weapons.

System requirements: 2 GHz CPU, 2GB RAM, GeForce3 or similar 3D card.
http://www.venomsoftware.de/games.php

Chex Quest 3

Chex Quest 3 is a free single-player FPS, released 12 years after original CQ by two original developers (Charles Jacobi and Scott Holman). It also includes two previous Chex Quests.

http://www.chucktropolis.com/gamers.htm

Tag: The Power of Paint

Tag: The Power of Paint is a DigiPen student-developed first-person platformer that won the Best Student Game Award in 2009. Tag is a mix of first-person shooter and puzzle game.

https://www.digipen.edu/studentprojects/tag/

Firestart

Firestart is reimaging of the classic C64 game, Project Firestart as a first-person shooter. It is set in the distance future when a ship orbiting Mars has been overrun by monsters.

http://earok.net/firestart 

Harmony

Harmony is a free FPS game made by Thomas van der Velden, that is inspired by nineties 3D shooters. This Zdoom engine based shooter features 11 maps and high resolution sprites.

http://rabotik.nl/harmony.htm

Resonation

Resonation is a first-person shooter that utilizes the frequency of sound waves for gameplay. Player has to solve mysteries and eliminate monsters utilizing the different frequencies.

https://www.digipen.edu/?id=1170&proj=452

Resident Evil Memory

Resident Evil Memory is a free indie first-person shooter video game tribute to the Resident Evil series. Resident Evil Memory features zombie killing and many puzzles.

System requirements: Pentium 4 2.66 GHz, 1GB RAM, 128MB Video Card.
http://residentevilmemory.blogspot.com/

WGRealms 2

WGRealms 2 is the free sequel to WG Realms. It is a standalone, fantasy style total conversion of DukeNukem 3D with new kickass weapons, inventory and abilities.

http://two.wgrealms.com/

Action Doom 2: Urban Brawl

Action Doom 2: Urban Brawl is the prequel to Action Doom with Beat-em-up’ style gameplay. This free shooter features over 15 weapons, 9 levels and dozens of new enemies.

http://action.mancubus.net/

Decay

Decay is a free-to-download horror first-person shooter with 6 action-loaded and exiting levels. You need to download a patch to change the language from German to English.

System requirements: Pentium 4 2.0 GHz, 512MB RAM, ATI Radeon 9600.
http://www.moddb.com/games/decay

Voxelstein 3D

Voxelstein 3D is a free FPS inspired by Wolfenstein 3D, with fully destructible levels. The world in this shooter is built from tiny cubes (voxels) that can be added or removed very quickly.

http://voxelstein3d.sourceforge.net/

Black Shades

Black Shades is a free simple first-person shooter which was one of the winners of the UDevGame 2002 contest. It features randomly generated city and fluid aiming system.

http://www.wolfire.com/black-shades  (also available for Mac)

Kill the avatars

Kill the avatars is an extremely small experimental FPS made for players entertainment. It is a shooter that takes all the fun of killing avatars and puts it all into nice little package.

http://www.moddb.com/games/kill-the-avatars

Get Bin Laden!

Get Bin Laden! is a free single-player FPS with small download size. In this shooter you have to shoot your way past dozens of enemies to locate Bin Laden's secret hideaway.

Minimum requirements: 500 MHz CPU, 64MB RAM, 32MB 3D graphics card.
http://www.atticgamez.com/Attic_Games/bin_laden.htm

Deadly Tower

Deadly Tower is a small experimental arcade first-person shooter made by two people with 36 hour production time. Deadly Tower has three playable levels.

http://www.moddb.com/games/deadly-tower

Half-Life 2: Lost Coast

Half-Life 2: Lost Coast is a playable technology demonstration that introduces HDR lighting to the Source engine. Lost Coast features one level that was removed from original Half-Life 2. 

System requirements: Pentium 4 2.4 GHz, 1GB RAM, DirectX 9 level graphics card.
ATI , NVIDIA

Avert Fate

In Avert Fate you fight killer droids with heavy weaponry, while exploring next-gen environment. This tech demo shows what a two-man team can do with Unity in a couple of months.

http://unity3d.com/gallery/live-demos/avert-fate

Cellfactor Revolution

CellFactor: Revolution is a tech demo that shows off the capabilities of the Ageia PhysX cards. Two levels in CellFactor are playable even if you don't have the PhysX accelator card.

System requirements: Dual core processor, 2GB RAM, ATI X1800+ / NVIDIA 7800+.
Download 

.kkrieger

.kkrieger is a free single-player first-person shooter that uses only 96KB (!!!) of disk space. This extremely small shooter won the Breakpoint 96k game competition in 2004.

System requirements: 1.5GHz CPU, 512MB RAM, 128MB GeForce4 Ti / ATI Radeon 8500.
http://www.theprodukkt.com/kkrieger

Flamewar!

Flamewar! is a satire about internet culture.

Download

Next list: Multiplayer FPS demos