Calvin and Hobbes by Bill Watterson for December 15, 1985
Calvin as Spaceman Spiff: We join our hero megazorks above the planet Gloob...Spaceman Spiff, conqueror of the cosmos, is pursued by the hideous scum beings of planet Q-B. Spiff's hyper-freem drive malfunctions! The aliens close in! Suddenly, a searing bolt of deadly frap ray slices across the blackness! Our hero is unfazed. Another bolt! Spiff is hit!! Spiff is going down! Can he make it?? Is this the end?!! AAAAAA!!! SPiff's alive! He made it!! I'm alive! HA ha ha! I kiss the sweet ground! Miss Wormwood: Maybe you should play on the swings, Calvin.