You and your clan must fight for control over the Forest of GrandBois by having the most presence and the most well-placed lookout tower.
After secretly drawing a clan in GrandBois, each player picks a forest tile, which depicts four forest squares that have 1-4 clan members of one of five colors, just forest, or a bear. They then add this tile to the rest of the forest, covering at least one-quarter of an existing tile. You can cover existing squares only if the covering squares have more clan members on them (or a bear as the bear beats them all).
You also have a tower you can place on an empty square of a tile that you just placed, scoring points for having clan members on adjacent tiles — but the sooner you place your tower, the sooner your opponents will have a big clue on which clan actually belongs to you!
