What if Hagane from Dai Majuu Gekitou: Hagane no Oni (Battle of the Great Demon Beasts: Demon of Steel) was in Super Robot Wars? An ability showcase. Dai Majuu Gekitou: Hagane no Oni is a single episode OVA combining suspense and mecha. Along with Dangaioh, the OVA descends from an earlier cancelled project called "Daimazinger", based on the Mazinger Z series. Whereas Dangaioh kept the action component, Dai Majuu Gekitou: Hagane no Oni instead keeps the drama. The OVA is set in and around a top secret isolated research facility; there, a new type of particle has been discovered and used to develop an orbital beam weapon. The story follows a former worker who returns to the facility after receiving a troubling letter from an old friend that remained there. For clarity, the subtitles here are not mine.