Moddable Chess · Variant 41 of 54

Patrol Chess

8×8Board 2Players

Patrol Chess

A piece may only capture or give check if it is “patrolled” — defended by at least one friendly piece. Isolated pieces are toothless.

Patrol Chess — starting position a b c d e f g h 8 7 6 5 4 3 2 1

Patrol Chess — starting position

Setup

Board: Standard 8×8.

Setup: Standard chess starting position.

FEN: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

Rules

  • Standard chess movement applies, with the following additions:
  • A piece may only CAPTURE if it is patrolled (defended by at least one friendly piece).
  • A piece may only give CHECK if it is patrolled.
  • Non-capturing, non-checking moves are played normally with no patrol requirement.
  • A piece is “patrolled” when at least one other friendly piece defends the square it occupies.
  • Checkmate requires the checking piece to be patrolled, AND the King has no escape to an unattacked square (where “attacked” also requires the attacker to be patrolled).
  • Castling and en passant follow standard rules (subject to patrol constraints).

Win Condition

Checkmate (the checking piece must be patrolled).

Strategy

Piece coordination is everything. Isolated pieces cannot capture or deliver check — they are purely positional. Keep pieces connected and defending each other. Knights near friendly pieces become deadly while isolated Knights are decorative. Development must be compact rather than spread out. A single undefended piece can safely sit in enemy territory since it cannot be captured by an unpatrolled attacker.

Attribution

Frederik Hendrik von Meyenfeldt, 1975. Public domain rules.