Lead Marvin, the Paranoid Android, through 42 levels of puzzles and solve the final riddle.
Every level operates under a specific set of rules that, once determined, will allow you to predict behavior of traps and enemies. The number of Marvin's moves depends on the amount of energy left in his batteries.
Don't be fooled by the simplicity at the beginning! Some levels further can be very challenging. See if you can beat it!