Double Dragon II: The Revenge/Versions

Mega Drive
Developed and published by Palsoft in Japan only. This game is a straight conversion of the original arcade game. However, the graphics and audio are of poor quality, even by Mega Drive standards, and the game suffers from several slowdowns. The jumping side kick is missing and all of the enemy characters are included with the exception of Jeff. The stages are the same as the arcade version, but some of the level designs are a bit different

NES
Developed by Technos and published by Acclaim outside Japan. Much like the first NES game, the game is merely an adaptation of the arcade version and is not a straight conversion. Unlike the first NES game, the sequel features 2-Players co-op with the option to enable or disable friendly hits. This version also features cut-scenes between stages featuring on-screen text and comic book-like artwork that narrates the game's story, three difficulty settings and a total of nine stages, some of them based on stages from the arcade version and others which are completely original. Almost all of the arcade version's enemy characters are present, with the notable exception of Willy, the arcade version's main villain. New enemy characters are added which includes the right-hand man and the ninja. A character simply referred as the "mysterious warrior" serves as the game's final boss in this version, with his battle taking place after the doppelganger fight. The ending is also different from the arcade version, in which Marian is restored to life after the mysterious warrior is defeated.

PC Engine Super CD-ROM
Developed by KID and published by Naxat Soft in Japan only. This port is essentially a remixed version of the NES game with elements from the arcade version. The cut-scenes are now animated and fully voiced. The stages are exactly like the NES version, with some changes to the level layouts. The weapons are from the arcade version, which includes the shovel and the iron ball. All the enemies from the NES version are included except for the right-hand man and the ninja (although their sprites were programmed into the game, they're never used), although Willy does make an appearance in this version.