Mysterious Chess is a game of placement. Each player has a deck of sixteen cards, with one card for each Chess piece in the Orthochess array. Players take turns placing cards facedown on squares of the board. When all cards have been placed, the cards are flipped over and play begins.
The game is conducted by rules of Orthochess, with the following changes:
Each player has a hand of sixteen piece cards: 8 Pawn cards, 2 Knight cards, 2 Bishop cards, 2 Rook cards, 1 Queen card and 1 King card. The backs of the cards should not be distinguishable from each other.
Placement goes as follows:
You can make up special cards for this game, or, if you have a Chess board with large squares, you could use a miniature pack of playing cards. In that case, use the red suits for white, and the black suits for black, and use the following mappings between cards and pieces:
Piece Cards King King Queen Queen Rook 10 Bishop Ace Knight Jack Pawn 2,3,4,5
The arrangement can turn out with the white and black pieces strongly mixed. Certainly if the players are restrained and place the cards defensively, the game will not start as all attacking. But if the cards (and pieces) are be mixed, the game can be unexpected and amusing.
Shuffle both sides cards and combine them into one pack. Players then place the cards one at a time from the combined pack without looking at the card's fronts.
Since the back of the cards are identical, the players do not know what type or color of piece they have placed on any square. It results in the greater randomness in the arrangement of the pieces.