Saisho Shogi

I decided to invent a shogi variant when I read Bushi Shogi page on  Georg Dunkel's blog. He said "I can't imagine a boardgame with one square and after that there is no more any board!" I took it as a challenge and I tought for months of inventing a new, smaller variant. I read about another Georg Dunkel's variant, Gufu Shogi, where there were shared pieces and I realized that that was the solution. Finally, in September 2019, I had a simple but effective idea: I could halve Dunkel's game by simply keeping the piece he invented, the bushi, almost unchanged, with only two or three differences. It would also have been shared by the two players, but there was still a problem: check and checkmate. This wasn't hard and I decided that the players would not be just maneuverers, they would be the targets.

The game took his form in my mind: there was an emperor with a flame in his hand; there were the players, who were talking to the emperor, both trying to convince him to become an ally; there were two cannons, each aimed at one of the players. There was Saishō Shōgi!

Setup

There is a single-square board, with two kanji writings at the extremities: 先手鉄砲 (Black's cannon) and 後手鉄砲 (White's cannon). These are used to mark the board direction, which is extremely important in this game.

(In this image, Black's side is on the bottom)

The board starts empty, with the Emperor in Black's hand. Black's first move is to drop the Emperor with the orientation he prefers, but without giving check or checkmate.

Pieces

The piece on the board

Emperor piece developement

Emperor: the piece is a cube with two kanji writings on every face: 天皇 (emperor) and 炎 (flame). You can move in these ways (from player's point of view):

• Rotating 90 degrees to clockwise
• Rolling to the front
• Rolling to the left
• Rolling to the right

Undoing the opponent's last move is illegal.

Rules

The game starts with Black dropping the Emperor with the orientation he prefers, but without giving check or checkmate; then White starts moving the piece and the two players alternate normally. When the flame is pointed towards you, it is check and you have to roll the cube to Emperor's look direction. When Emperor's look is pointed towards you too, it is checkmate and you lose. Giving yourself check is legal, but giving yourself checkmate is not.

If the game exceeds one hundred moves (fifty moves for each player), the one who gave more checks wins (self-check counts as a check from the opponent).

Last revised by Francesco Fonseca.