Introduction:

Sundraval (from Gothic: Sundrawald, meaning "separated territory") is a drawless game for two players: White and Black. It is played on the intersections (points) of an initially empty hexagonal board. The recommended size is 9 points per side, but it can be played on a 11–sized board for longer games or a 7–sized board for shorter games. Each player has access to a sufficient supply of stones of their own color.

Definitions:

– A group is a set of connected stones of the same color. A single stone is also a group.
– A territory is a set of uninterrupted empty points bounded by stones of a single color that fill all adjacent locations.
– A path is a set of N uninterrupted empty points (where N can be zero).
– A strangled group is a group that, at the end of the game, meets the following 3 conditions:

1. There is a path from there to larger enemy groups or with territory.
2. It has no territory, nor a path from there to non-strangled friendly groups.
3. There is no path from there to smaller enemy groups that are strangled.

Turns:

Black plays first and then alternates. On your turn, perform one of the following actions:

– Place a stone of your color on an empty point that has a path to enemy groups.
– Pass your turn.

End of the Game:

The game ends when both players consecutively pass their turn.

Immediately before scoring, remove all strangled enemy groups from the board. Then, each of a player's groups with N adjacent territories earns (N^2 + N) / 2 points, i.e., according to the triangular number. In addition, the player with the group that contains the largest territory receives a half point extra (or the next largest).

The player with the total value of groups with territories in their possession wins.

To make the game fair, before it begins, the first player places two initial stones, one black and one white, at any empty point on the board, and the second player chooses the sides. This balancing method is called the two-stone pie rule.

Notes:

Special thanks to Drew Edwards and Dale Walton who valuable contributions to improve key aspects; Drew Edwards optimized a key rule, while Dale Walton refined the wording.

–description from designer