Quake 2 Map Info is a command line utility that parses a Quake 2 map file and reports how many entities and textures are being used. It is useful for spotting extra items to improve gameplay balance and/or reducing extra textures to increase map speed. Most map editors do not provide a detailed breakdown of what is inside a map. It is compatible with any Quake 2 (ID Tech 2) game engine if the map file format has not be altered. If a game has a different map format, you can modify the source code to reflect the new format.
The Castle is a first-person shooter game in a dark fantasy setting. Your main weapon is a sword, so the fight is mostly short-range. Three main levels are included, packed with creatures, items, and sounds. A couple of bonus levels are also available, like the classic DOOM E1M1 level reimplemented in VRML. The game engine is based on VRML, OpenGL, OpenAL, and all shadows are done by the shadow volumes approach.
Sauerbraten (a.k.a. Cube 2) is a free multiplayer/single player first person shooter, built as a major redesign of the Cube FPS. Much like the original Cube, the aim of this game is not necessarily to produce the most features and eye candy possible, but rather to allow map/geometry editing to be done dynamically in-game, to create fun gameplay and an elegant engine.
Crystal Core is a FPS quest-based game written with Crystal Space and Crystal Entity Layer. The game is based on a science fiction story. The player and his or her companions crash on an alien planet where they discover that the original intelligent inhabitants are now extinct due to an invasion of semi- primitive aliens from a distant planet. Your goal is either to destroy all aliens or escape the planet alive. To accomplish these goals you have to use alien technology and try to interface it with the broken ship that you arrived with.
Alpha Shooter is a 3D first-person shooter game with a sci-fi setting. It features multi-platform support (Linux, Mac OS X, CygWin, and Windows) and, since version 0.1.0, its own reusable game engine (Neutron). The game and its engine will evolve over time to incorporate simulated physics and AI, networking, audio, scripting, and more.
Warsow is a standalone, eSports-oriented FPS game. It is based on Qfusion, an advanced modification of the Quake 2 engine. It features fast-paced gameplay focused on trix (trick jumps) and art of movement. War§ow features a complete power-up system, including weak and strong fire mode for each weapon in all "normal" gametypes as well as Warshell (battle shield) and Warshock (quad damage) for team-based gametypes. Its cartoonish graphics use cel shading with a style that is similar but not identical to Manga.
Nexuiz is a fast-paced, chaotic, and intense multiplayer first-person shooter game, focused on providing basic, old style deathmatch. It is extremely modder-friendly. Nexuiz is built on the power of the Darkplaces engine, which is a heavily modified version of the original Quake. Darkplaces features realtime lighting and stencil shadows, bumpmapping, gloss, bloom, and totally rewritten network code that supports up to 64 players on a single server.