While each of these instances was likely influenced by Dark Horse’s staff being fond of the radio dramas, they also fit into the stories they were telling quite naturally. Stackpole and Steve Crespo, and Mara Jade’s whereabouts in Return of the Jedi were depicted in Star Wars: Mara Jade - By the Emperor's Hand by Timothy Zahn, Michael A. Narra’s death in the Battle of Derra IV was shown from the Empire’s perspective in an Star Wars: X-Wing Rogue Squadron issue by Michael A. Commander Narra also appears in Empire, fighting alongside Luke Skywalker and recruiting the Clone Trooper Able to the Rebellion in a two-issue story arc by Ron Marz, Nicola Scott, and Adriana Melo. Leia’s mission to Ralltiir shortly before the events of A New Hope was adapted line-for-line in an issue of Star Wars: Empire by Randy Stradley and Davidé Fabbri. Likely due to both the Legends continuity being the official Star Wars timeline when Dark Horse’s stories were being published and the appreciation for the radio dramas by their creators, the three adaptations’ original content was referenced by several comics. Related: Luke's Connection to Vader Began Much Earlier Than Fans Know Return of the Jedi’s radio adaptation wouldn’t be released until 1996, but thanks to the resurgence of non-movie content in the '90s, it featured numerous Legends-era references, including a brief appearance from Mara Jade in Jabba’s Palace, based on dialogue from the Thrawn Trilogy. The Empire Strikes Back radio drama in 1983 also included an extended opening, with Luke Skywalker’s friend and mentor Arhul Narra perishing along with his X-Wing squadron during the Battle of Derra IV. This includes an alternate opening sequence, beginning with Luke Skywalker and his friends on Tatooine and Princess Leia’s Rebel mission to Ralltiir, and ending with Leia’s active role in the theft of the Death Star plans during the Battle of Toprawa.

1981’s Star Wars radio drama had the largest number of new additions to the film it’s based on.

Star Wars by Michael A. Stackpole