Moving the Pieces
Figure 4: If you look at figure 1, you can see that the white and blue views are essentially 8x8 grids just like a normal chess board. If you remove the 3d distortion you get the odd diamond shaped boards pictured above. Notice that each triangular grey zone space is depicted on both the blue board and the red board. This will make sense if you look at figures 2 and 3, but means that if you are playing on a "diamondized sphord" you can't simply count pieces on the board. For example there is only one g6 pawn and one f7 bishop, but you can see them each duplicated on both boards.
anyway... PAWNS! as you can see in figure 4, they actually work pretty much exactly like in orthochess except:
- There is no jump move
- Pawns promote on the 7th and 2nd ranks instead on 8th and 1st
- Pawns on the a, b, g or h files can can never promote unless they move further into one of the colored zones by capturing on, make a capture within the promotion zone.
Figure 5: Rook movement in sphere chess is pretty straightforward, except now the ranks and files curve around to form rings around the board. If the rook moves forward (dark green arrows) it eventually ends up behind where it started, because there are no pieces on the c file to impede its progress. The same thing happens if it tries to move backwards. The rooks movement is still impeded by both running into friendly pieces and capturing opponent pieces, thus this rook is unable to circumnavigate in the third rank.
Hello fellow variant enthusiasts! I recently posted a nigh incomprehensible info dump on my own deranged chess variant played on an orb instead of a board. You can view the original blog post here: https://www.chess.com/clubs/forum/view/spherical-board-chess
I am back with more mad ravings to shout into the void.
Opening Setup
Figure 1: The biggest drawback of spherical chess when compared to orthochess is obvious in that you can only see 1/2 of the playing surface at a time. My previous 3d renderings of the sphord were jarring and I feel hard to understand. However, all squares on the sphord (spherical board) can be depicted in 2 views, in this case one view from the red side of the sphord and one from the blue side of the sphord. There is the added benefit that reducing the game to a 2d format may allow an eventual adoption on chess.com.
Figure 2: As you can see the red and white views are not the only 2d perspectives one can create for the sphord. One could rotate the sphord on a vertical axis to view it form the kingside or the queenside as well. Here we see that colored squares have 4 sides and have duplicates of the opposite color (eg there is 4b-red and 4b-blue). Grey triangles on the other hand have no duplicates and bridge the gap between the red and blue zones (there is only one f2 space). Note that from this view the ranks can be represented linearly, but the files are resented as rings of polygons radiating out from the a and h files. The closer you get to a bisecting plane of the sphere the more cells each file has. The a file has only 2 cells, while the d file has 14 cells.
Figure 3: Rotating the sphord toward or away from the viewer gives the white and black views of the sphord. These views give the most obvious perspective on the opening setup for each side. Just as in orthochess, the white king and queen start on e2 and d2 respectively. With the only 2 cells on the first rank now full, the minor pieces and rooks live on the second rank, forming a perimeter around their regents. Spherical chess has 10 pawns instead of 8. The all start on the 3rd rank and there are 4 red zone pawns and 4 blue zone pawns. The grey zone pawns on the g and b files may choose to advance into either of the two colored zones.