Twinmove Chess

a fully practicable double-move chess

Twinmove Chess, initial position


Twinmove Chess is a double-move variant. The objective is to capture the enemy king. The double-move consists of a pawn move followed by a piece move, which is mandatory. There exist two variants of Twinmove Chess. In one variant pawn moves are compelled, until there exist no more pawn moves, when the pieces can continue moving without being preceded by a pawn move. Should a pawn become free to move again, it is compelled to move. In the other variant the player may forfeit the pawn move, and instead move a piece, but then he has lost his double-move.

Note that a player, when the king is threatened, can make a pawn move before taking measures to protect the king. He can also make a pawn move that discloses his king to an enemy piece, but he is well adviced to protect his king in the subsequent move. This implementation only allows promotion to queen. The en passant rule does not exist, simply because a pawn move cannot occur prior to the opponent’s turn. Games always begin with a pawn move, otherwise the rules are the same as in orthodox chess. Somewhat surprisingly, this is a sophisticated and fully functional form of chess.


What makes this game so interesting is that pawn moves are both for good and bad. It’s not always advantageous to move a pawn. This circumstance creates a strategical tension in the game. Pawn moves often cause irreparable damage to the position. In the variant with compulsory pawn moves, to be forced to make that extra pawn move could sometimes be regarded a punishment, rather than a reward. In the variant with uncompelled pawn moves the situation is less acute, since one is not forced to weaken one’s pawn chain in critical situations. The positional laws of chess are fully valid in the uncompelled variant, although the double-move creates interesting tactical possibilities, both in defense and attack. The missing en passant move facilitates the defense, as a counterweight to the forceful attacks occuring in this chess variant. Note that a pawn can promote to queen and immediately move, since it satisfies the condition of pawn move + piece move. Don’t give up if you’re losing material. There are many opportunities for counterattacks in this game.

Game Alchemy

It is surprising how easy it is to create fully practicable chess variants. It can be viewed almost as an art form, nourished by chess variant societies, like the British Chess Variants Society, chess variants journals, and webpages like The Chess Variants pages. It is reminiscent of medieval alchemy, an activity that mixed rational "scientific" content with imaginative creations. It is something about this mixture which is quite compelling.

Looking closer at the central notions of medieval alchemy, we find striking similarities with our occupation with board games/puzzles. The focal point in alchemy was the Vas Hermeticum, the alembic, or the alchemical retort, which are all different names for the alchemist’s vessel where the warring elements were subjected to heat and underwent circular distillation. In the gaming business the board, as such, is the equivalent of the hermetic vessel, while in it the warring elements are added and sealed off from the outside world. In alchemical manuscripts it is depicted as the coniunction of Sol et Luna, Rex and Regina, winged and wingless dragon, etc. The latter bite each other’s tail, forming a circle, symbolic of the process. The same idea is also portrayed as the Uroboros, the tail-biting serpent.

In alchemy, the circular distillation implies that dissolutio (the forming of vapour) follows upon coagulatio (the forming of substances on the bottom of the retort) in a circular motion. I came to think about this mythologem when I developed Bario, which uses a recycle concept. However, the cyclic motion is, in itself, a more general symbol. It implies the maintenance of a transformative process in a substance that from the beginning lies inert. The goal of the process was the appearance of a spiritual substance, i.e., the alchemist’s gold, or the red elixir, etc. From the chaos, the prima materia, of crude material substances, will arise a refined spirit, the Spiritus Mercurius, the Stone of the Philosophers, which had wonder-working properties.

My point is that, unconsciously, board gamers follow the alchemists’ procedure as they focus on the transformations in their vessels, which are the game boards. This is essentially the same as the alchemist’s labourings with his chemicals. So we are in fact trying to synthesize the most holy substance from our games. I think that involved in this work is a phantasy of "The Perfect Game." We are searching for the game that will have wholesome effects on the ones who play it; that will make them healthy, bestow on them long lives, and also have benevolent effects on the surrounding world.

Ancient and medieval people viewed board games as doorways to the spritual sphere. I believe this fantasy is still at work in our unconscious. But unlike the ancients, modern people are generally unaware of the spiritual aspects of things. In order to understand what’s behind the historical obsession with board games, it is necessary to develop a better insight into symbolic and archetypal themes. Game diagrams were often carved into temple walls and roofs. In Gloucester Cathedral, according to H.J.R. Murray, there are several Fox and Geese boards incised on the stone seats. From the well in Norwich castle (a holy place) was retrieved a game scratched on a flat stone. Fox and Geese boards also occur inside, and on the outside walls of, the cloisters of San Paolo, Rome.

In India, according to Prof. Rangachar Vasantha, board games are depicted in murals, and they were deliberately built into roofing slabs, or the floor of temples in ancient India. In the temple at Kurna in Egypt there are more than 70(?) board games painstakingly carved into the roofing slabs. Almost every tenth artefact found at Mohenjo-daro in Pakistan (built around 2600 BCE) is game related, including different forms of dice and playing pieces (Rogersdotter, 2011). The historian Johan Huizinga ("Homo Ludens") says that taking part in contests and games have been a very central aspect of culture, especially in China. According to Rigsthula, Viking children trained swimming and the playing of tafl. In the Aztec kingdom, nobles were often seen walking through town with a Patolli board under the arm. I hold that the board game is symbolic of a spiritual mystery, a vessel in which the spirit is captive, and this is where our fascination stems from.

  You can download my free Twinmove Chess program here (updated 2006-05-02), but you must own the software Zillions of Games to be able to run it.

  Try playing Twinmove Chess (compulsory) by e-mail, against a human opponent, here.

  Try playing Twinmove Chess (uncompelled) by e-mail, against a human opponent, here.

  Don’t miss my other chess variants.

© M. Winther 2006