Star Wars Adventures: Return to Vader's Castle 5 depicts the rescue of Thom Hudd from his imprisonment on Fortress Vader, which began during the events of Star Wars Adventures: Tales from Vader's Castle. According to 
Cavan Scott on the Ghoulactic Horrors of Tales from the Death Star on StarWars.com (backup link), Tales from Vader's Castle takes place around the events of Rogue One: A Star Wars Story, which immediately precedes Star Wars: Episode IV A New Hope, the ending of which is dated to 0 ABY by Star Wars: Timelines. Since the events of Rogue One and A New Hope occur in the span of days, and Star Wars Adventures: Ghosts of Vader's Castle 3 mentions that Thom Hudd was imprisoned on Fortress Vader for months, the frame stories of Star Wars Adventures: Return to Vader's Castle, which span together in a very short period of time, must all occur on 0 ABY at the earliest.
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The events of [[ISSUE]] take place in [[YEAR]] according to the reasoning [[:Template:ReturnVadersCastle|here]].