Commander Keen 5: The Armageddon

Commander Keen 5: The Armageddon Machine is, for many fans, the high point of the whole series. Part of the second trilogy, Goodbye Galaxy, it was released in 1991 and finds Billy Blaze infiltrating the Shikadi's Omegamatic space station to destroy the titular doomsday device before it can blow up the galaxy. It runs on id's more advanced Keen engine, a clear step up from the original Vorticons games in both looks and design.

This entry shows the level design at its most inventive. Keen navigates the station's sectors in any order, riding teleporters, dodging the sparkling Shikadi and their electric barriers, and using the pogo stick to reach devious secret areas. The Sphereful and other enemies force careful timing, and the balance between platforming precision and light puzzle-solving is judged beautifully. The animation and parallax backdrops were genuinely impressive for a PC platformer of the period.

What elevates episode five is the atmosphere and the confidence of the whole package: memorable music, a real sense of place aboard the station, and a difficulty curve that rewards mastery without feeling cheap. It holds up far better than most early-nineties PC platformers, and if you only play one Keen game to understand why the series is so beloved, this is the one to choose.