''Alien Arena'' (initially ''CodeRED: Alien Arena'') is an
open-source
Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized so ...
, stand-alone
first-person shooter
First-person shooter (FPS) is a sub-genre of shooter video games centered on gun and other weapon-based combat in a first-person perspective, with the player experiencing the action through the eyes of the protagonist and controlling the p ...
video game. Begun by COR Entertainment in 2004, the game combines a 1950s-era
sci-fi
Science fiction (sometimes shortened to Sci-Fi or SF) is a genre of speculative fiction which typically deals with imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, parallel universe ...
atmosphere with gameplay similar to the ''
Quake'', ''
Doom
Doom is another name for damnation.
Doom may also refer to:
People
* Doom (professional wrestling), the tag team of Ron Simmons and Butch Reed
* Daniel Doom (born 1934), Belgian cyclist
* Debbie Doom (born 1963), American softball pitcher
* ...
'', and ''
Unreal Tournament
''Unreal Tournament'' is a first-person arena shooter video game developed by Epic Games and Digital Extremes. The second installment in the '' Unreal'' series, it was first published by GT Interactive in 1999 for Microsoft Windows, and late ...
'' series. ''Alien Arena'' focuses mainly on
online
In computer technology and telecommunications, online indicates a state of connectivity and offline indicates a disconnected state. In modern terminology, this usually refers to an Internet connection, but (especially when expressed "on line" ...
multiplayer
A multiplayer video game is a video game in which more than one person can play in the same game environment at the same time, either locally on the same computing system ( couch co-op), on different computing systems via a local area network, or ...
action, although it does contain single-player matches against
bots
The British Overseas Territories (BOTs), also known as the United Kingdom Overseas Territories (UKOTs), are fourteen territories with a constitutional and historical link with the United Kingdom. They are the last remnants of the former Bri ...
.
''Alien Arena'' has been released for
Microsoft Windows
Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for ...
,
OS X
macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and la ...
,
Linux
Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, whi ...
, and
FreeBSD
FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD), which was based on Research Unix. The first version of FreeBSD was released in 1993. In 2005, FreeBSD was the most popular ...
. While the game's content is