Cube

Cube is a multiplayer and singleplayer first person shooter game. Cube is a landscape-style engine that pretends to be an indoor FPS engine using a combination of techniques. Allows in-engine editing of geometry in full 3D, which can even be done simultaneously with others in multiplayer. Has simplistic but effective fine grain vertex lighting that looks like lightmapping and can do dynamic lights & shadows. Doesnt need any kind of map precompilation, even lighting is done on the fly.It has very simplistic quad-tree world structure that can do slopes (heightfields with caps) and slants, water, does decent collision detection and physics, has client or server networking that goes a long way in giving a lag-free game experience, and features a singleplayer (2 game modes, savegames) and multiplayer (12 game modes, master server or server browser, demo recording) game with some uncompromising gameplay.