Keen 6 Story
Commander Keen 6: Aliens Ate My Baby Sitter! is set some time after Keen 5. The events of Keen 6 are considered a diversion from the main plot of the rest of the series. This is in quite a literal sense, since the abduction of Molly McMire by the Bloogs would likely buy Mortimer McMire time to advance his malevolent scheme to destroy the universe.
McMire's plan was simple: create a situation which Commander Keen would have to respond to, but, should Keen succeed, would not provide any setbacks for himself. And he had the perfect means of doing so. The Bloogs, a species of rather dim-witted and hunger-driven aliens from Fribbulus Xax, were very easy to convince. All McMire had to do was give them the location of the Stupendous Sandwich of Chungella IV, and they would do what he asked. It was then that the Bloogs set out to abduct Keen's baby-sitter, Mortimer's sister, Molly. (Whether they all planned to share either the sandwich or Molly for dinner is unclear; most likely is that the Bloogs did not think it all through.)
The timing and mechanics of the abduction were carried out perfectly. Molly was taken away by the Bloogs while she was baby-sitting Keen. When Keen ran outside to see what had happened, he found a note which told where Molly had been taken, and further elaborated that she was to be eaten by the Bloogs. Keen, as McMire had expected, went to the aid of his baby-sitter.
Rescuing Molly proved to be a major challenge. Fribbulus Xax was well-populated by all manner of hazardous creatures, including, of course, the Bloogs themselves. Still, Mortimer, never one to make things too easy, made sure the planet was extra-ready for Keen's arrival. With any luck, this little diversion would kill Keen.