Aliens: Countdown is a 14-part comic book short story that was first published by Dark Horse Comics in the promotional publication Dark Horse Insider, Vol. 1 #14-27, from September 1990-October 1991. Published in black and white, the story was written by Mike Richardson and illustrated and inked by Den Beauvais. The comic serves as a tie-in to the four-issue series Aliens: Nightmare Asylum.