Games similar to Alien Swarm include Doom. It's paid, but Digital Paint: Paintball 2 is free. Other options are Shadow Warrior (Reboot), Prodeus, Dead Space and HELLDIVERS. You can choose from more than 10 First-Person Shooters like Alien Swarm for Windows, Linux, Mac, the web and Android.
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.
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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.
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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.
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Dead Space is a survival horror third-person shooter video game for Microsoft Windows, PlayStation 3 and Xbox 360.
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HELLDIVERS is a topdown shooter set in a satirical dystopian future where mankind is ruled by a managed democracy. You are part of the Helldivers – the spearhead of humanity’s defense against the perpetual alien threat on Super Earth.
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Killing Floor is a co-op survival horror FPS game. Remake of the UT2004 modification and available on Steam platform.
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Killing Floor is a "Total Conversion" mod for game. Playing as a squad of marines, you must use firepower and teamwork to drive back massive hordes of bloodthirsty zombies.
Digital Paint: Paintball 2 is a Paintball game that started out as a mod for quake 2 but then took on a life of its own as an open source fps game with a global player and clan management system.
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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
Set in the iconic Alien universe, Aliens: Fireteam Elite is a cooperative third-person survival shooter that drops your fireteam of hardened marines into a desperate fight to contain the evolving Xenomorph threat.
United States
Zandronum is a multiplayer oriented port, based off Skulltag, for Doom and Doom II by id Software.
Dead Meets Lead is every bit and piece of what a challenging zombie-slaying action game should be. Enter the role of the 18th century commander who’s on a mission to obliterate evil, by fighting your way through the island of El Mirando.
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