Hifuu OS: Immersive hacking simulator based on the Touhou Project. Play as Renko Usami, learn and use authentic terminal commands to hack into the Great Hakurei Barrier. Unravel the truth behind Maribel Hearn's mysterious coma as you search through Gensokyo's secret and private documents.

　　Fully Immersive

　　Hifuu OS boots your computer into a vintage terminal-based machine from the 1980s. The purely text-based user interface brings you right back to the wild west of the early days of the Internet, where security loopholes floated all over the place. Communicate with in-game characters and progress the game via the built-in email.

　　Engaging Stories

　　Uncover the truth behind Maribel Hearn's mysterious coma as you search through private files from computers used by Gensokyo's residents and organisations. Accept the invitation from the lunatic elite hacker team EagleSec, alter the cybernetic world within the border as you see fit, and become a Gensokyo cyber outlaw.

　　Real Experience

　　Take the Kyoto University Computer Security 101 course as Renko, and learn the knowledge of using Unix commands to navigate and manage file systems applicable both in the game and in the real world. Familiarise yourself with a series of computer security concepts and practices while hacking into weakly-protected systems.