Yapsan's Spherical Chess on Game Courier

Yapsan's Spherical Chess is an adaptation of Chess to a spherical board in which the files meet at the poles, and pieces are capable of both transpolar and circumpolar moves. While not the earliest Spherical Chess variant, it was an original attempt that differed from its predecessors in important respects. It is the earliest known Spherical Chess variant to give the Bishop a limited colorbound move that can loop around the board without intersecting with itself until it reaches the space it began on. It is also the only Spherical Chess variant to explicitly allow a Bishop, Rook, or Queen to move to its starting space if it can make a complete loop around the board without any obstruction. Yapsan calls these stationary or infinite moves. It is also the first known one to give Knights eight possible moves from any space on the board and to allow castling in either direction with either Rook.

This preset enforces the rules, displays legal moves, and spots winning and draw conditions. To make the visualization of transpolar moves easier, it can be played on a display of two hemispheres. You can rotate them by choosing the files they meet at. They can be seen side-by-side in a landscape display or one-over-the-other in a portrait display. Desktops will default to the landscape display while mobile devices will usually use the portrait display, but you can set it to what you want. This game can also be played on a regular Chess board, which can make other moves easier to visualize. You can switch which type of board you're viewing the game on by changing themes.

Click the image for the preset: