Tirnabun 2024

Tirnabun (from Scottish Gaelic: tìr na buidhne, meaning "territory of group") is a strategy game for two players: Black and White. It is played on the hexes (cells) of an initially empty hexagonal board. The recommended size is 7 cells per side, but boards with 5 or 9 are also valid. Each player has access to a sufficient supply of stones of their own color.

Definitions: A group is a maximal set of connected stones of the same color. A single stone is also a group. The size of a group is the number of stones it contains. A territory is a maximal set of connected empty cells. You own a territory if the largest adjacent group belongs to you, and in case of a tie, the next largest groups are compared; if all are the same size, the territory does not score for either player. A live group is a group that either has at least one adjacent empty cell that is part of the friendly territory, or, if it does not have adjacent empty cells, is equal to or larger in size than the adjacent enemy group; otherwise, it is a dead group.

Turns:Black plays first and then turns alternate. On your turn, place a stone of your color on an empty cell not adjacent to groups of any color, unless the largest adjacent enemy group is exactly the same size or exactly one stone smaller than the group of the placed stone.

End of the game:The game ends when neither player can place stones. The player with the highest score wins, calculated as one point for each empty cell within friendly territories plus one point for each stone in dead enemy groups.

To balance the game, before starting, the first player places a black stone on an empty cell, and the second player chooses a side. This balancing method is called the pie rule.

—description from the designer