This local eight-by-eight game enforces forward men, short kings, global capture priority, and crown-stop. Separate Chain and Crown presets expose the two rule boundaries without pretending the sparse positions arose from a normal opening.
Use the worked example
Load Chain and select row 2 column 1, then 4, 3 and 6, 5. R1 takes W1 and W2 and Red wins the sparse position. Load Crown separately: 5, 0 to 7, 2 crowns R3 and ends Red’s turn even though a backward king jump would otherwise be available.
Trace the result step by step
The movement rules follow the WCDF English rules: forward-moving men, short kings, compulsory captures, and crown-stop. This page supports local play and illustrative positions. Its resignation and mutually accepted draw controls do not implement tournament clocks or automatic repetition adjudication.
Use an eight-by-eight zero-based row/column board. A square is playable when (row+column) modulo 2 equals 1. Start Red's twelve men in playable cells of rows 0–2, White's twelve in rows 5–7, with Red first. Red advances toward increasing row values; White advances toward decreasing values.
For this declared model, a man moves one forward diagonal into an empty playable cell. A king may move one diagonal forward or backward. A jump passes over an adjacent opponent into the empty cell immediately beyond, following the piece's allowed directions. There are no flying kings or backward jumps by uncrowned men.
At the start of a turn, inspect all current-player pieces for legal captures. If any exists, the legal-action set contains captures and no quiet moves. Selecting a piece without a capture cannot make its ordinary moves legal. Keyboard users can activate a square with Enter; after selection or a move, focus stays on that square’s replacement button. A pending draw offer clears when the opponent’s first legal action is accepted, including the first jump of a longer capture.
Reject a light-square destination, occupied landing cell, wrong-owner piece, wrong turn, or unsupported direction without altering the position. Selection and helpful feedback may change, but pieces, captured IDs and current player do not.
R1 jumps from (2, 1) to (4, 3) over W1. From (4, 3), another forward jump reaches (6, 5) over W2. The landing cells are empty and playable. R2 has no capture here; its quiet move is blocked by R1's available capture.
After the first jump, Red's turn remains locked to R1. Selecting R2 cannot take over the chain, and a quiet destination is rejected. Jump R1 to (6, 5) to complete the capture sequence. The two captured IDs disappear only when the sequence finishes.
The Chain preset contains only two White pieces. R1's second capture therefore ends that example with a Red win. Reset restores the ordinary twenty-four-piece opening; it does not continue from the reduced Chain position. Use the preset name when discussing a result so the two boards are not confused.
Use another independent position: Red man R3 at (5, 0), White W3 at (6, 1), White W4 at (6, 3), other cells empty. R3 jumps to (7, 2), captures W3 and reaches Red's king row.
Copy a prompt for this example
Build one HTML page containing an original two-player checkers board with the declared American/English-style movement rules. Use zero-based row and column coordinates. Playable squares have an odd row-plus-column sum. Red starts with twelve men in rows zero through two; White starts with twelve in rows five through seven. Red moves toward larger rows.
Men move and capture diagonally forward; kings use short diagonal moves and captures in either direction. If any current-player piece can capture, reject every quiet move. Continue multiple jumps with the same piece. Keep captured IDs pending and occupied until the sequence ends, preventing repeat captures. Reaching the king row crowns a man and ends that turn.
Provide a Chain preset: R1 at (2,1), R2 at (2,5), W1 at (3,2), W2 at (5,4). R1 must jump to (4,3), then (6,5), removing White's final pieces. Provide a separate Crown preset: R3 at (5,0), W3 at (6,1), W4 at (6,3). Jumping to (7,2) crowns R3 and passes the turn without an immediate backward jump.
Use labeled square buttons, piece IDs, an explicit king symbol, and legal-destination feedback. Loss follows no pieces or no legal move. Include resignation and a draw offer requiring the opponent's acceptance. Reset restores the full starting board. Keep the eight-column board readable on a narrow screen and return all HTML, styles, and game code in one file.
Keep the declared rule variant and sparse positions beside the implementation when reviewing changes. Preview the HTML board in NOS if useful for that discussion. Ask the reviewer to identify the legal next actor after each jump, particularly the newly crowned piece’s completed turn.