A number of comic books based on (and continuing) the story of "Aliens" have been published (primarily by Dark Horse Comics) since 1988. Dark Horse published a crossover of the titular aliens and those of the "Predator" franchise by 1990, creating a derivative "Alien vs. Predator" franchise with its own films, video games and comic books; this led to additional crossovers with Superman, Batman, Green Lantern, Judge Dredd, Wildcats, and the "Terminator" franchise. Reebok's boots designed for Ripley became available to the public in 2016; other versions included boots based on the power loader, Bishop, the Colonial Marines and the alien queen. Author J. W. Rinzler published "The Making of Aliens", a 300-page behind-the-scenes book with cast and crew interviews and previously-unseen photographs, in August 2020. "Operation Aliens", a board game, was released in 1992. Players as cast as a Colonial Marine or Ripley and tasked with finding a self-destruct code to destroy an infested spaceship.