A 3D Spot the Difference: A Novel Spatial Puzzle, small worlds is an immersive puzzle game that challenges players to identify discrepancies between two seemingly identical three-dimensional environments. By leveraging the depth and perspective afforded by three-dimensional space, the game introduces a new layer of complexity to the classic spot-the-difference formula. Players are presented with a pair of visually similar 3D scenes that can be manipulated, rotated and zoomed in, to reveal subtle differences. This interactive exploration encourages critical observation and spatial reasoning as players meticulously examine every angle and detail to uncover the disparities. The game's 3D nature offers a more engaging and challenging experience compared to traditional 2D variants, demanding a higher level of visual acuity and spatial awareness from players.