Yume Nikki (“Dream Diary”) is a surrealist adventure game made with RPG Maker 2003 by Kikiyama, a pseudonymous Japanese developer. It was first shared on the Japanese textboard 2channel on June 26, 2004, and updated until version 0.10 in 2007. The player controls Madotsuki, a girl who lives alone, and explores her dreams. There is no dialogue, no combat, no plot, and no way to reach a game over.
At first she cannot leave her apartment. Writing in her dream diary at the desk saves the game; sleeping in her bed begins a dream. Outside the dream version of her room lies a hub, commonly called the Nexus, lined with doors, each leading to a completely different area. The only objective is to collect twenty-four “effects” scattered through the dream world. Collecting them all unlocks an ending in which Madotsuki jumps from her balcony.
An English fan translation brought it a global cult following. Its open-ended, combat-free exploration is described as a precursor to the walking simulator, and its pixel art and horror elements as an influence on indie horror games such as Ao Oni and Ib. Kikiyama was unreachable from 2011 to 2018, fueling speculation that they had died, until the 2018 reboot Yume Nikki: Dream Diary confirmed that they were alive and involved.