About the Manufacturer
ADK (Alpha Denshi Kabushiki kaisha) was founded in 1980 in Saitama Japan. It partnered with SNK, now known as SNK Playmore, and was a manufacturer of video games, mostly famously the World Heroes Series.
ADK made games for many genres, including maze games like Crush Roller, sports like Champion Baseball, shooters like Time Soldiers, platformers like Blue's Journey, role-playing games like STED: Iseki Wakusei no Yabou, fighting games like the World Heroes series, and beat 'em up games like Gang Wars and Ninja Combat. The company became quite famous, with considerable success in North America.
However, through the mid to late 1990s, ADK failed to win very much success, especially during the eras of the Neo Geo Pocket and Neo Geo Pocket Color handheld systems, which were also failing at the time. The company eventually went bankrupt and closed its installations in early 2000 (SNK itself would declare bankruptcy the very next year). SNK's successor, SNK Playmore, ended up buying ADK's intellectual properties.