The Triangular Foundation is one out of two foundations available in the game. Using the Triangular Foundation, the player may build diagonal lines on the raft. If the Shark attacks a Triangular Foundation, the player can destroy the foundation with an Axe and rebuild it instead of repairing it. Doing this uses no Material.
Building Triangular Foundations does not count towards the Builder! achievements.
- Can be used to expand the Raft diagonally.