In the early 2000s, before high-speed internet and social media dominated Vietnamese youth culture, a low-quality, pixelated horror game spread like wildfire through网吧 (net cafes) and cracked-CD collections. That game was “Mouse ke san nguoi ngoai truyen” — colloquially known as “Mouse” — a terrifying urban legend disguised as a video game. What is “Mouse ke san nguoi ngoai truyen”? Contrary to its literal translation (“Mouse tells the story of a vampire” or “The Mouse that tracks people”), the game has no mice and no vampires in the traditional sense. It is, in fact, a bootleg, unofficial Vietnamese-translated version of "The House of the Dead" (Sega, 1996) or a similar light-gun arcade shooter, heavily modified with local folklore elements and creepypasta-style rumors.

A fascinating artifact of early Vietnamese gaming culture — part technical failure, part collective imagination, and entirely legendary. There is no ghost. There is no fourth level. But if you find an old CD labeled “MOUSE” at a flea market… some say you should leave it there.