Benedict Chess

There are no captures. When a piece moves to a square from which it attacks enemy pieces, those pieces convert to the mover’s colour. Win by converting the opponent’s King.

Benedict 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

Pieces move as in standard chess but there are NO captures.
When a piece moves to a new square, every enemy piece it now attacks (could move to, if it were a capture) immediately converts to the moving player’s colour.
Multiple enemy pieces can convert from a single move.
Pawns convert enemies on the diagonals they attack, not the square in front.
The King can be converted — this ends the game immediately.
Since there are no captures, the total number of pieces on the board never decreases.
No castling (the King is too vulnerable to conversion near the centre).
No en passant (there are no captures).

Win Condition

Convert the opponent’s King to your colour (by moving a piece that attacks the King’s square).

Strategy

Long-range pieces (Queen, Bishops, Rooks) are enormously powerful because they can convert many pieces at once. The game snowballs — converting pieces gives you more attackers. Protecting your King from being in ANY attack line is critical. Early moves are decisive; one careless move can trigger chain conversions.

Attribution

C. S. Elliott, 1971. Named after Benedict Arnold. Public domain rules.