Darren Provine at Rowan University

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Schrödinger's Chess

Schrödinger's Chess is set of variations I made up after reading Iain M. Banks's book The Player of Games.

The changes are as follows:

  1. The rooks, bishops, and knights are concealed in some way (opaque covers placed over the pieces, or the pieces replaced with salt shakers that have the piece written on tape stuck to the bottom, or similar). Which piece is which cannot be seen by the opponent. The player had better remember which is which.
  2. The six concealed pieces go in the usual locations, but can be placed in any arrangement by the player.
  3. While concealed, the pieces can move one or two squares in any direction.
  4. Revealing a piece is considered a move. Once revealed, a piece moves according to the traditional rules.
  5. If a piece is captured while still concealed, it remains concealed until the game is over.
  6. A concealed piece is considered "concealed", even if the other five concealed pieces have been revealed and there is no longer any doubt about what it is.
  7. To castle, a rook must be uncovered and must be in either (a) or (h). Uncovering the rook doesn't count as a separate move for the purposes of castling.

An interesting variation would be to cover the pieces in such a way that a player knows his own pieces but the opponent does not. Then each player puts the other's pieces on the board. So you don't get to choose where they go, but you do know what they are.

The pieces being able to move 1 or 2 squares in any direction while concealed does make them very powerful (moreso than knights, for example), but knights can jump and concealed pieces can't. Similarly, rooks and bishops have reach, which concealed pieces don't. One suggested variation from some Slashdotters is that concealed pieces can move one or two squares in any direction, but they can only capture like kings. I'd be really interested in hearing from anybody who tries a few games and reports back on how they like it.

The name comes from the famous thought experiment about the cat. To the opponent, each covered piece has to be considered a potential rook, a potential bishop, and a potential knight, until the uncertainty collapses when it is revealed.

If you give this a try, let me know.