3139: Chess Variant

2025-09-09T03:07:59Z

2600:1700:94A0:6BE0:655E:B4D4:F27E:65BC: /* Explanation */

{{comic
| number = 3139
| date = September 8, 2025
| title = Chess Variant
| image = chess_variant_2x.png
| imagesize = 310x344px
| noexpand = true
| titletext = The draw-by-repetition rule does a good job of keeping players from sliding a tile back and forth repeatedly, but the tiles definitely introduce some weird en passant and castling edge cases.
}}

==Explanation==
{{incomplete|This page was created recently by an IMMOVABLE CHESS BOARD. Don't remove this notice too soon.}}
A {{w|Sliding puzzle|sliding puzzle}} is a puzzle with movable pieces that challenges players to slide the pieces around the board to get them into a certain pattern or to move a certain piece into a certain position. Patterns can be anything from a completed image to a series of numbers. One of the most common variants, the {{w|15 puzzle}}, is a square board with 15 square pieces (usually numbered 1 through 15, but can also feature pictures) and one empty space in a 4x4 grid. The goal is to order the numbers (or reassemble the picture) without lifting any piece, only sliding pieces into the empty space. [[Randall]] contemplates making a {{w|Chess variant|variant of chess}} in which sections of the board can be moved around, possibly as an alternative to moving your own pieces. It is possible that "sliding number chess puzzle" is a pun on actual {{w|chess puzzles}} in which pieces are set up in a position and the player must find the best move or sequence of moves in that position.

The title text states that because of the {{w|threefold repetition}} rule in chess, sliding a tile back and forth will result in a draw, and this will make the game more interesting as some people don't want to draw. Also, with the tiles, ''{{w|en passant}}'' pawn capture and {{w|castling}} is weird, due to deciding whether moving a tile counts as moving a piece and thus making it ineligible for castling, whether a pawn is eligible for ''en passant'' capture if a tile has moved (rather than the pawn), and where the pawn goes after an ''en passant'' capture. It's also unclear whether pieces are allowed to move through empty spaces where there is no tile.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[A chessboard is shown with the white pieces at the bottom of the screen. The pieces are illustrated in the basic design of standard computer chess. The chessboard is divided into 16 2x2 sliding squares with the e3-f4 sliding square currently being moved to the g3-h4 spot. Otherwise the opening is a standard Scotch Opening, with the pieces in the e3-f4 spot like how they are supposed to be]
:[Text below the panel]
:Sliding number puzzle chess

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3139: Chess Variant