Dark Prison is a game set in the Super Robot Taisen Original Generation (OG) universe, focusing on the development of the story from the main series. It centers on the battles between different factions of robots, as well as the confrontation with the darkness threatening the world. The main characters are Kyosuke Nanbu and Ryusei Date from the Granteed team, a special task force assigned to combat the threats posed by an enemy group known as Dark Prison. This group is a coalition of organizations with the goal of destroying the world and opening a gateway to another dimension. The story focuses on the war between these factions, as well as resolving internal conflicts within the alliances tasked with protecting the world. Each character undergoes development, with complex relationships and narratives that play a crucial role in uncovering the truth about the enemies they are fighting.