Holy Diver is a side-scrolling action game for the Famicom, released by Irem in Japan on April 28, 1989. Set in the 666th year of a magical world, the Red Kingdom faces invasion by the Dark Empire’s demon lord Black Slayer. The 16th Red Emperor, Ronnie IV, entrusts his young sons Randy and Zakk to loyal retainer Ozzy before his death. The three flee to another dimension, hoping to return and drive out the darkness. Seventeen years later, Randy and Zakk have grown into powerful mages, but Zakk vanishes and Ozzy passes away. To save the kingdom, Randy sets out alone to find five Red Family crests and defeat Black Slayer. The game has six levels; players control Randy through forests, castles, caves, and more, fighting enemies and bosses. Each level grants Randy new magic—double flame, freeze, rock break, super speed, thunder, and others. Players also collect items like bracelets, jump boots, a magic staff, and a protective cloak to boost Randy’s abilities. It is quite challenging, with diverse enemies including demons and flying eyeballs. Its music and character names draw heavily from heavy metal: protagonist Randy is named after guitarist Randy Rhoads, and other characters/locations reference rock music. Since it was only released in Japan initially, it became a rare collector’s item. In 2018, Retro-bit re-released the NES version worldwide for the first time, with an English translation.