Star Wars Legends media such as games and comics feature a number of specialized stormtrooper units. The Marvel-produced comics of the late 1970s and early 1980s featured Shadow Troopers. Other specialists have included commandos and troopers equipped to work in the vacuum of outer space, such as the zero gravity Spacetroopers depicted engaging in extra vehicular battle in the 1991 novel Star Wars: Heir to the Empire, and its 1995 Dark Horse Comics adaptation.