Alien Arena is a fast paced multiplayer deathmatch game similar to Quake and Unreal Tournament, but with a deep sci-fi atmosphere, lot's of shiny and weird graphics and... aliens. The engine is based on the CXR game engine, but has been rewritten to allow a lot of new features and improvements such as 32bit high-resolution textures. The physics is based on the Quake II physics, but also allows dodging. It also features single-player matches against bots. View a YouTube demo here.
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Nexuiz Classic is a fast-paced 3D deathmatch game with high-end and complex graphics effects. It is intended to be played over the Internet or over a local network. Several different game types, such as classic deathmatch, team deathmatch and capture the flag are available. It also supports a single-player mode and playing against the computer. View a YouTube demo here.
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OpenArena is a community-produced deathmatch FPS based on GPL idTech3 technology. There are many game types supported including Free For All, Capture The Flag, Domination, Overload, Harvester, and more. View a YouTube demo here.
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Quake III Arena
The true legend. Quake III Arena is a multiplayer shooter focusing on competitive matches, be it duel, capture the flag, instagib, deathmatch,... It has defined modern tournament shooters and still has an active community. The portage version uses the ioquake3 engine which is kind of a fork based on the source code release of the original Quake III in 2005. There are tons of mods and extension packs available in portage (such as games-fps/quake3-matrix or games-fps/quake3-nsco), as well as a data ebuild (games-fps/quake3-data) and a demo ebuild (games-fps/quake3-demo). View a YouTube demo here.
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Urban Terror is is an open-source multiplayer first person shooter based on the ioquake3 engine. It can be described as a hollywood tactical shooter; somewhat realism based, but the motto is "fun over realism". This results in a very unique, enjoyable and addictive game which reminds of Counter Strike, but is more action and speed oriented. View a YouTube demo here.
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A fast paced open-source multiplayer shooter based on the QFusion engine. It is similar to Quake3, but is set in a futuristic cartoonish world. Warsow is all about speed and movement and features known game types like capture the flag or instagib. View a YouTube demo here.
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Xonotic is a a free and fast-paced deathmatch FPS based on DarkPlaces, an advanced Quake 1 engine. It is a direct successor of the Nexuiz project and combines arena-style gameplay with rapid movement and a wide array of weapons. It could be considered most similar to Unreal Tournament and Quake at its heart, especially regarding teamplay and game mechanics. It features 18 official maps and many community contributions, has a lot of different game modes and claims to provide e-sports opportunities. It also provides an integrated statistics system called XonStat. View a YouTube demo here.
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