MusicThis game was originally to have music created by Commander Keen composer Bobby Prince, but the music was scrapped at the last minute to make it all fit on one disk. This is why the song entitled "Eat Your Veggies" is in Commander Keen 4: Secret of the Oracle.
SeriesThis is sometimes referred to as the "Lost Episode" of Commander Keen. According to Joe Siegler of Apogee, he called it Keen Episode 3.5. The reason stated for this is that the game falls between the Invasion of the Vorticons series (Episodes 1-3) and the Goodbye Galaxy series (Episode 4 and 5).
SoftdiskUnlike the other Keen games this game was not published by Apogee but by Softdisk. The id developers were all former Softdisk employees and when they formed id, the group still had the obligation to produce a couple of games for Softdisk.
Information also contributed by Roedie and Tony Gies