over the board that are disconnected and not immediately helpful for forming pentes and other powerful patterns. Stretch tria A stretch tria is a shape formed by a single stone placed in line with a pair of stones and a single empty space between them. The stretch tria is vulnerable to counter because an opponent can place a stone between the single stone and the pair and threaten capture. It is powerful however because it threatens to form a tessera, and if unbound on either side forces the opponent to respond in a similar way to open tria, creating initiative and allowing play elsewhere on the board without the opponent interfering. The stretch tria can be a very powerful tool when used in conjunction with other stretch trias. A vertical stretch tria with the pair at the top and the single stone at the bottom can be combined with another stretch tria in a diagonal or horizontal line so that both stretch trias share the same single stone. If an opponent tries to stop one of them, then the very next turn, the player who formed the stretch tria can extend the other and turn it into a tessera. If the tessera is unbound the position is likely a winning one Open tessera An open tessera is a line of four stones in any direction without any of the opponent's stones on either side. If the open tessera isn't cut across with certain captures that dismantle it, it can't be stopped from forming a pente and winning the game for the player who formed it. The reason for this is that if an opponent tries to place a stone on either of the sides, the attacking player can simply place a stone at the opposite end and form a pente. Advanced shapes Advanced Pente play often utilizes more complicated shapes built from basic shapes in order to achieve initiative and positional advantage. Among the most common are the I, L, h, X, and H shapes along with the 4x3 pattern, the 5x3 pattern, and the Hat. The I The I shape is a stretch two unbound on either side and with the space to expand to an L shape in at least one of the applicable directions. The l shape, like the stretch two, protects your two stones from being captured as a pair, and has the ability to threaten