The actor who portrays the devil, Michael Berryman, is best known for portraying the character, Pluto, in Wes Craven's The Hills Have Eyes (1977).
In the very first scene, Jonathan and Mark are paying homage to a scene from Twilight Zone: The Movie when Jonathan says to Mark, "You wanna see something REALLY scary?" (Originally said by Dan Aykroyd).
Michael Landon was born on Halloween in 1936. This Halloween episode aired just one day before his 49th birthday.
Even though it is Halloween (colors orange and black), the devil arrives in a pink mist, bathed in a pink light; his horns and face are finished with pale pink make-up, and his a black cape is lined in bright pink, which he has paired with a pink bow-tie. Pink is the color of the heart ("love"), and was a dominant color throughout the show. (Christians say "God is love".) Perhaps this was to indicate neutralizing the Devil's impact from the characters and/or his symbolic negative energies from the viewing audience.
RD Robb plays the Little Devil boy; he is known for his role as Schwartz in A Christmas Story (1983) which came out two years before his episode.