On March 20, 1995, the Tokyo Metro experienced a horrific terrorist attack carried out by the cult Aum Shinrikyo. Members of the cult released sarin gas on five trains, resulting in the deaths of 13 people at the scene, with a total of 1,000 to 5,000 injured. This attack, the deadliest in Japanese history, led to significant changes in public transportation regulations to enhance safety. The investigation also brought attention to Aum Shinrikyo's dark activities, including the creation of a video game with a disturbing premise.