There will not likely be any further releases.
Unreal (1998) is a highly enjoyable classic FPS with some rough edges. Unreal Evolution seeks to address these and bring a high quality golden age game to the next level. Expect tighter overall design through polished and enhanced weaponry/gunplay, smarter artificial intelligence and refined enemy placement, Enhanced Artistic Direction (new textures, effects, level details), tightened balance and resource distribution, new player mechanics, an engaging challenge (of course based on the difficulty mode you pick), enhanced replayability, audio design upgrades, a handful of bugfixes, better bossfights, level design with more to offer without being obviously different, and more...If you've played my critically-acclaimed 'GMDX' mod for Deus Ex, you know what to expect. Unreal Evolution is intended to enhance the overall experience yet retain the original spirit and concepts: Unreal but better
Unreal Evolution Trailer: