Balance Shogi

One player places both kings; the other chooses to be Sente or Gote. The first-move advantage is balanced by the players themselves, not by a number in the rulebook. Play it here, against the AI or a friend, right in the browser.

Play Balance ShogiNothing to install. The home screen opens with Balance Shogi selected.

What it is

The base game is Fuseki Shogi: both sides place 20 pieces each on an empty board, then ordinary shogi begins on move 41. Fuseki Shogi favours Sente, who wins a little over 60% of games between AIs. Balance Shogi does not cancel that with a numeric handicap; it balances it with the first two placements and one choice.

Furigoma decides who places both kings; the other player chooses the side. Everything else is Fuseki Shogi, except that your rook and lances may not share a file of your camp (the Nihikyō restriction).

1. Placer
   Move 1 — the Sente king
   within Sente’s four ranks
2. Placer
   Move 2 — the Gote king
   within Gote’s four ranks
3. Chooser
   ☗ Take Sente☖ Take Gote
   Choose a side
   the position does not change
4. Sente & Gote
   Moves 3–40 — the rest
   19 each, alternately from Sente

The placer does not yet know which side they will play. Put the Sente king in a safe spot and the chooser takes Sente; make it too thin and they take Gote. The placer only breaks even when the gap in king safety exactly matches the first move. It is the pie rule — one cuts, the other picks first — and the balance point is set by the players on the day.

What you can do here

• Play the AI. Take either role, placer or chooser, or let furigoma decide. The AI places and chooses from a table that measured all 1,296 king pairs. Pick its strength and the time control.
• Play a friend. Send an invite link. Nothing to install on their side either, and the same link brings you back.
• Lobby. Post a seek anyone can join, or join one.
• Game record and analysis. An evaluation graph and analysis after the game. Export the record; it keeps both who placed the kings and who was Sente.

Play Balance Shogi

Read more

The placement zone, the nifu-avoidance and Nihikyō restrictions, the move-41 adjudication and the AI's table are in the rules. Why the king squares alone are enough, and how the balance was measured, is in How Balance Shogi came to be.

Japanese name: 天秤将棋 (tenbin shōgi, "scale shogi"). Fuseki Shogi and Balance Shogi share one board screen; switch between them on the home page.