Before the game white puts a ninth white pawn outside the board, on the, so to speak, a0 strip, while black puts a ninth black pawn on, so to speak, a9 strip.
Now they play a standard game of chess except that white can move its pawn from a0 to a2 whenever a2 square is unoccupied, while black on its move can move a9-a7 whenever square a7 is unoccupied. But remember, that one still needs to answer a check. Once you move your extra pawn onto the board, you don't have any extra piece in the reserve, and from that moment only classical moves are available to you.
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In general, the two players have to agree on which specific version of resChess they want to play. Then they put the extra pieces (but never a king) on the strips a0 ... h0 and a9 ... h9, in the quantities agreed upon, but the pieces have to be proper for their columns: pawns can be on any strips but rooks only in a and h, knights only in b and g, etc.
Then, whenever the original square of a piece is vacant, say b1, then one can play there the respective piece, say a knight: Nb0-b1. Yes, on the same strip b0 you may agree to have any number of pawns and knights. However, it doesn't feel like fun to me to agree on a really big bunch of reserve pieces.
The pieces on the strips have to be easily seen by both players (any attempt of hiding them would amount to cheating).
- Even 1 extra pawn in strip a already potentially affects stalemate positions.
- It's interesting to play with the reserve consisting of one rook on a0 h0 and on a9 h9. Then I'd think twice before castling. BTW, one may castle with any of their rooks, as long as that rook never moved from its initial board square, and other conditions should hold too.
- Wlod
