Adanaxis is an action game where the fundamentals of space itself are changed by adding a fourth dimension to space. Initially, it's like learning to play a 3D FPS for the first time, as the hand and eye have to learn a whole new type of coordination. The gameplay involves rapidly blowing things out of the sky, with the usual assortment of enemies, allies, weapons, and power-ups, together with commercially sourced graphics, audio, and voice acting.
Aleph One is a 3D first-person shooter game based on the game Marathon 2 by Bungie Software. It is set in a Sci-Fi universe dominated by deviant computer AIs and features a well thought-out plot. Aleph One was originally a MacOS game, but a cross-platform version ("Aleph One/SDL") based on the Simple DirectMedia Layer (SDL) library is currently under development which runs under Unix, BeOS, and Windows.
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.
BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS 10.x, Irix, Solaris, and others. An OpenGL accelerator is highly recommended, but it is playable with 3D in software.
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.
Dreams Eternal is an FPS game that focuses on a strong story line and puzzle solving. It is set in the dream world. The very short summary of the story is that a scientific experiment went wrong and everybody is stuck in the dream world. You have to end this experiment by hopping from dream to dream. In every dream you have to find clues to try to find out how the experiment can be aborted.