A prototype codenamed Downfall Zero was once made on Agetec's RPG Maker II for Sony's PlayStation 2 by ƒJosh. It served as the basis and foundation for Downfall FES. Not much is known about this prototype, as it was never released publicly due to many reasons. Many features from the prototype, such as a nameable protagonist and 3D platform puzzles, are not present in Downfall FES.