Alien Swarm is described as 'Free top-down shoot-em-up video game by Valve Corporation. It is a remake of the Alien Swarm mod for Unreal Tournament 2004, and it was developed by the original team, which was hired by Valve during the course of the development process' and is an game in the games category. There are more than 10 games similar to Alien Swarm for a variety of platforms, including Windows, Linux, Mac, Steam and Playstation apps. The best Alien Swarm alternative is Doom. It's not free, so if you're looking for a free alternative, you could try Digital Paint: Paintball 2 or Dead Meets Lead. Other Alien Swarm like games are Prodeus, Shadow Warrior (Reboot), HELLDIVERS and Dead Space.
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.
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.
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.
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.
Dead Space is a survival horror third-person shooter video game for Microsoft Windows, PlayStation 3 and Xbox 360.
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.
Killing Floor is a "Total Conversion" mod for Unreal Tournament 2004 game. Playing as a squad of marines, you must use firepower and teamwork to drive back massive hordes of bloodthirsty zombies.
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.
Zandronum is a multiplayer oriented port, based off Skulltag, for Doom and Doom II by id Software.
Jake2 is a Java 3D game engine. It is a port of the GPL’d Quake2 game engine from id Software. To use the Jake2 engine you need either the data files from the original game or from the demo version that is available for download from ftp://ftp.idsoftware.com.
Killing Floor is a co-op survival horror FPS game. Remake of the UT2004 modification and available on Steam platform.
Nightmare Creatures is a survival horror video game released for the PlayStation and PC in 1997, and Nintendo 64 in 1998 as a North America exclusive. It was developed by Kalisto Entertainment and published by Activision.
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