Ao Oni

The game's plot focuses on a boy named Hiroshi and his friends investigating and becoming trapped in an old mansion said to house a monster, with him having to escape as the monster hunts him down. Aooni gained a cult following in Japan and overseas due to livestreams and playthroughs. Aooni has received multiple sequels and spin-offs, and has been adapted into a variety of media, including three feature-length movies, a series of light novels, a manga and an anime series. A remaster was released on Steam and Nintendo Switch in 2024 and on Playstation 5 in 2026.

The player controls Hiroshi as he explores the locked mansion, gathering items and solving puzzles in order to escape. The Aooni will begin to chase the player at both random and at certain scripted moments throughout the game.

A teenage boy named Hiroshi, along with his classmates Takuro, Takeshi, and Mika, investigates a mansion on the outskirts of town that is rumored to house a monster. They discover the Aooni, described as a naked, blueberry-colored giant who pursues the group. One by one, each of Hiroshi's classmates dies in the mansion, becoming infected with a virus that transforms them into another Aooni. Hiroshi continues to explore the mansion, solving puzzles and evading the Aoonis as he seeks a way to escape.

Aooni was first developed in 2008 by Japanese indie developer noprops with RPG Maker XP. noprops had developed various puzzle games during and after Aooni's development such as Escape from the Haunted Room and White Room. Four versions of the game were released until the game's final release in 2011; these versions differ drastically in terms of plot, map layout and puzzles. A spider-like Oni was planned to be added as an enemy in the third released version, but was scrapped due to difficulty in giving it an natural-looking walk animation.

Aooni has been adapted into a variety of media, including novels, two live-action films, anime and manga.