Check out Grant Acedrex, our featured variant for April, 2024.

This page is written by the game's inventor, Rich Hutnik.

Simultaneous Chess

This game is an attempt to adopt the basic essence of what is seen in simultaneous Connect Four, to Chess.  The rules to Simultaneous Connect Four can be seen here:

In a nutshell, rather than players alternating turns, players both select their moves secretly at the same time, and then resolve.


As in normal chess.  Randomly determine which player will have the initiative.


Same as in regular chess.  Players also need a way to record their moves and reveal.  A token to mark who has initiative is also needed.


The rules are nearly identical to normal chess.  However, player select moves simultaneously.  Players win if they checkmate their opponent, or capturing enemy king.  Player is not permitted to move their king into check.  This is done as follows:
1. Players randomly determine who the player with the initiative is, and that player gets the initiative token.
2. Players secretly record their moves and both reveal.  Players check to see if their moves would be legal before player moves.
3. Player with initiative moves their piece first (pieces in case of castling), then player without initiative moves their piece(s).  In case where player.  In case where player moving second makes and illegal move, as a result of the action of the player with the initiative's move, then that player forfeits their movement, but becomes the player with the initiative.  The moves players attempt to make before turn begins must be legal before both players make their moves. 
4. Examples of moves that are considered illegal that cause change in initiative:
A. Player without initiative attempts to move piece onto same space that first player moved their piece onto.  To capture, a player must move a piece that was on the space the prior turn, and not onto space currently.
B. Player without initiative attempts to move pawn to capture a piece that just moved.  Besides the pawn all other pieces moving are considered capture moves.  Such a move can include the pawn attempting to capture a pawn of a player with initiative, which is capturing the pawn attempting this (in this case, the player with initiative captures pawn of player without initiative, but initiative passes).
C. Player without initiative attempts to move their king into into a space that would result in check after player with initiative moves piece.
D. Player without initiative attempts to move a piece just captured by player with initiative.
5. Player with King in check must attempt to move king.

In a nutshell any attempt to do what would be an illegal move would result in player without initiative forfeiting their move and gaining initiative.


Simultaneous Connect Four has played real well.  It will be interesting to see how it plays out in chess.  It is entered here for review and evaluation.

A suggested variant for this game would be to break movement up into two phased.  First, players select and reveal which piece(s) they will be moving, then reveal where they are moving to.

This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.

By Rich Hutnik.
Web page created: 2009-04-08. Web page last updated: 2009-04-08