Freedoom: Phase 1 contains four episodes, nine levels each, to provide a smoothly-paced first person action game. In it is a wide variety of mazes and enemies to fight and challenge your reflexes.

The Freedoom project aims to produce three base-game data files (IWADs) for Doom-compatible engines. With it comes the capability to also play the wide range of mods created for Doom by a vibrant community. Freedoom: Phase 1 is fully compatible with The Ultimate Doom mods.