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This page is written by the game's inventor, H. G. Muller.


Decimaka is a western Chess variant that tries to emulate the promotion dynamics of the historic Japenese Chess game 'Maka Dai Dai Shogi'. In particular, promotion is not reserved for Pawns. Most piece types from the initial setup can promote, and the right to promote originates from making a capture, rather than reaching a promotion zone. So promotion can happen everywhere on the board.

This makes tactics highly non-trivial. It also impacts strategy, because promotion at the end of a game is not automatic, and in fact impossible if the opponent would not have any easy targets for capturing.

Note: a revised version of this game, with somewhat tweaked rules, is described here




The game is won by checkmating the opponent King. Stalemate is a draw.

Pieces can (and sometimes must) promote when they make a capture. This can happen anywhere on the board, there isn't any special promotion zone. Promotion is mandatory when you capture a promoted piece; otherwise it is optional, and you can elect not to promote.

A piece other than King which captures a Queen promotes to Queen in the same turn. That also applies to pieces that are already promoted, or would normally not promote at all.

Pawns that reach the final rank simply turn into dead wood there.


There are three classes of pieces, depending on how they promote:

Promotability has a huge affect on tactics. Where without it an exchange typically is most profitable whan you capture with the least-valuable piece first, with it you would try to end with the piece that has the best promotion. Furthermore, when you won't make the last capture yourself, you can sometimes try to discourage the opponent's recapture by promoting (if he can only recapture with a strongly demoting piece). Which is a reason to order unpromotable pieces earlier, even when they are more valuable.

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 H. G. Muller.

Last revised by H. G. Muller.

Web page created: 2018-03-13. Web page last updated: 2018-03-13