How to Play the Game of Y
The Game of Y, invented independently by Claude Shannon and by Craige Schensted and Charles Titus, is Hex's triangular cousin: one group, three sides, no draws.
The rules
- The board is a triangle of 45 hexagonal cells, nine along each side. Red moves first.
- Players alternate placing one stone on any empty cell. Stones never move and are never captured.
- You win when one of your connected groups touches all three sides of the triangle. Corner cells belong to both sides they lie on.
- No draws: a full board always contains exactly one winning group.
- Swap: after Red's first stone, Blue may swap colours instead of placing a stone. The stone becomes Blue's and Red moves again.
Playing on kawu
Tap an empty cell to place a stone; the Swap colours button appears for Blue's first turn. Hint shows the hard computer's move. Play either colour against three levels, or two players on one device. Undo is allowed.
Next: Game of Y strategy.
Frequently asked questions
Do corner cells count for two sides?
Yes. A corner lies on both sides that meet there, so a group containing a corner already touches two sides and needs only the third.
Why does the second player get to swap?
Going first is a big advantage in Y. If Red opens in the centre, Blue can take over that stone instead of answering, so Red is encouraged to open somewhere modest.
Last updated 2026-10-21