Yume Nikki is a free indie video game created by Kikiyama in 2004. The game follows a young girl named Madotsuki as she explores her dreams. Players navigate through various surreal dream worlds, each filled with unique environments and strange characters. The objective is to collect "effects" that grant Madotsuki different abilities and alter her appearance. The gameplay is non-linear and emphasizes exploration and discovery. There are no enemies or traditional goals, allowing players to immerse themselves in the dreamlike atmosphere. Yume Nikki has gained a cult following for its unique art style and open-ended narrative, inspiring various fan interpretations and adaptations.