Harvest Moon 3D - The Lost Valley (USA) (Japanese: ハーベストムーン3D ロストバレー), is a farming simulation game developed by Marvelous AQL and published by Natsume for the Nintendo 3DS. It is the first game in the Harvest Moon series to be released on the 3DS. The game follows the traditional Harvest Moon formula, with the player taking on the role of a young farmer who must manage their farm and build relationships with the other villagers. The game features a new 3D graphics engine, new crops, a larger variety of animals, and a new 'Lost Valley' feature that allows the player to customize the terrain. The game also features online multiplayer, allowing players to share their farms and compete against each other. Harvest Moon 3D - The Lost Valley is a fun and engaging game that will appeal to both veteran and new players of the Harvest Moon series.