Commander Keen 4: Secret of the Oracle (1991) is a part of the popular Commander Keen saga, developed by id Software, and is the first episode of Commander Keen in Goodbye Galaxy.
Several months after the freeing the Vorticons from Mortimer McMire, Commander Keen (Billy Blaze) finds out that an unknown race called the Shikadi are planning to destroy the Milky Way. He sets course towards Gnosticus IV on a quest to discover their location with the Oracle's aid. Upon arrival, he discovers that the Shikadi have captured the Council Members. In order to save the universe, Keen must fly to the Shadowlands and rescue them.
Using a series of tricks listed in the submission text, Keen reaches the ending in a mere 10 minutes.
Be sure to also watch the exciting conclusion to Goodbye Galaxy.