1 <p>The board is rotated by
45°, and then the game follow usual rules.
</p>
3 <p>Pawns move forward "one diagonal", and capture forward "orthogonally".
</p>
7 <a href=
"https://www.chessvariants.com/rules/diamond-chess">
13 <p class=
"author">James Alexander Porterfield Rynd (
1886).
</p>