Double Dragon II: The Revenge, from 1988, picks up the Lee brothers shortly after the events of the original Double Dragon, now with Marian's death as the story's trigger. It keeps the two-player cooperative base that made history in the first game, but polishes the combat system with more moves and a more cinematic staging, including an opening scene that marked an entire generation.
Along with the original, it's one of the founding stones of the modern beat 'em up: the genre owes this Technos saga a good part of its basic grammar -side-scrolling cooperative combat- that Capcom, Konami, and Sega would exploit throughout the following decade.

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