Green with Envy, The Revenge and The Soothsayer's Secret by Eddie MountainGoat.
Written as additional "episodes" of the animated series, these two stories include elements of the game as they would have been portrayed in the animated series, up to keeping a family-friendly writing style. "Green with Envy" deals with a series version of Jeff (the green Palette Swap of the Lee brothers in the games) being recruited by Shadow Master. "The Revenge" is a loose adaptation of Double Dragon II, though Marian is frozen instead of killed. "The Soothsayer's Secret" is an adaptation of the first stage of the NES Double Dragon III, with the Neo Shadow Warriors led by Jesse Jim, the brother of Wild Willy, working for Shadow Master.