Trivia
The opening sequence (with the words floating by each other) is a parody of the opening sequence of the movie "The Terminator". When you select "Return to Demo" from the options screen, the story that's shown is an obvious parody of the "Star Wars" scrolling text opening sequence.
The song "Eat Your Veggies" in the Well of Wishes level actually was written for Keen Dreams, but was removed from that game to save disk space. Explains the name, now, doesn't it?
Easter Eggs:
1. a) Start a new game of Keen 4.
b) Go to the Moon Pyramid, named Pyramid of the Moons.
c) Step on a moon drawing on the floor.
d) Wait. Instead of his idle habit of reading a book, Keen will "Moon" you! Only works once per gamefile.
2. a) Go to the Pyramid of the Moons.
b) Climb down the second pole to the right.
c) Go in the door and press B, A, and T simultaneously, which will give you the yellow gem automatically.
d) Go right and unlock the door.
e) Walk further right and hit the switch.
f) Walk around slowly back and forth to each side of the whole room, so all the inch worms collect around your feet.
g) A huge foot will appear. Touch it and it takes you to the secret level.
h) Beat this level, and read the janitor joke that appears.
Developer Tom Hall on the creating the infamous Dopefish:
"The Dopefish, upon reflection, is pretty much based on one of two little faces my brother, sister, and I would draw on everything. Except stuck on a fish. I guess they were sort of the emoticons of the seventies. And of course, he's inspired by the Ravenous Bugblatter Beast of Traal from The Hitchhiker's Guide to the Galaxy. That's why they're the SECOND dumbest creature in the universe."
(excerpt taken from 3D Realms website)
Billy Blaze (AKA Commander Keen) is actually William J "BJ" Blazkowicz's (of Wolfenstein 3D fame) nephew.
There was a special version released specifically for CGA, as the EGA/VGA version didn't support CGA.
Keen 4 was bundled with the Gravis PC Gamepad
Secret of the Oracle is the first of two episodes of the series Commander Keen: Goodbye Galaxy!. The other episode is "The Armageddon Machine".
Unlike Commander Keens 1 through 3, Commander Keen 4 supported CGA graphics through a special version.
