Gomoku

Gomoku is a fun game.

You use black and white stones. You play on a grid. Players take turns placing one stone. The first person to make five stones in a row wins.

The line can be straight. It can also go slant. This line must be unbroken. You can win with a line that goes side to side. You can win with a line that goes up and down.

Sometimes the board fills up. If no one has five in a row, it is a draw. This means no one wins.

People play this in many lands. It is popular in China and Korea. You can even play it with paper and a pencil!

Gomoku is a game of strategy. Its name comes from Japanese. "Go" means five and "moku" means pieces.

Players use black and white stones. They place them on a grid. Usually, the grid has 15 by 15 spots. In the past, boards were larger. You win by making a line of five stones. This line can be flat, tall, or slanted.

Some rules say a line must be exactly five stones. If you make six stones, it is an "overline." In those rules, an overline does not count as a win.

Black always moves first. This gives Black a big advantage. To make the game fair, players use special rules. One rule is called Swap2.

In Swap2, the first player places three stones. These are two black and one white. Then, the second player chooses their color. This helps balance the game.

Many countries love this game. In China, it is called Wuziqi. In Korea, people call it Omok. You can even play it with paper and a pencil!

Gomoku is a fascinating game of strategy. Its name comes from the Japanese language. In Japanese, "go" means five and "moku" means pieces.

People around the world play this game under different names. In China, it is called Wuziqi. In Korea, it is known as Omok. In the nineteenth century, the game even reached Britain. There, it was called Go Bang. This name was likely a mistake. It came from the Japanese word "goban," which means a Go board.

Playing the game is simple but requires deep thought. Two players take turns placing stones on a grid. These stones are usually black and white. Most players use a board with 15 by 15 intersections. In the past, a 19 by 19 board was more common. Players place their stones on the empty spots where lines cross. The goal is to form an unbroken line of five stones. This line can be horizontal, vertical, or diagonal.

Some rules say a line must be exactly five stones long. If a player makes a line of six or more, it is called an "overline." In those versions, an overline does not count as a win.

History shows that Gomoku grew in popularity long ago. Its origins trace back to the Edo period in Japan. This was during the mid-1700s. A skilled merchant named Kuwanaya Buemon helped the game spread. He was the tenth generation of his family. By the late Edo period, around 1850, people were writing books about it. The earliest verified book on the game was published in 1856. Because the stones do not move once they are placed, people can even play it with paper and a pencil.

In many games, the person who goes first has a huge advantage. In Gomoku, the black player goes first. This can make the game feel unfair. For a long time, championships used a "Pro" opening rule. This rule required the first player to place their first stone in the center. In the 1989 and 1991 world championships, black won 67 percent of the games. To fix this, tournaments adopted the Swap2 rule in 2009. In Swap2, the first player places two black stones and one white stone. Then, the second player chooses which color they want to be. This makes the win ratio about 52 percent for the first player. This change makes the competition much more balanced.

There are many different ways to play this game. One version is called Renju. It uses extra rules to help the second player. For example, Black cannot make two rows of three stones at once. Another version is called Ninuki-renju. This version adds a way to capture stones. You can capture a pair of stones by sandwiching them. This is called "custodial capture." You can also play Pente, which is similar but uses a larger board.

These different styles show how much people enjoy the challenge of the game.

Gomoku is an abstract strategy board game centered on pattern recognition and tactical planning. The name comes from the Japanese language, where "go" means five and "moku" is a counter for pieces. The objective is simple yet deep: players compete to form an unbroken line of five stones of their color. This line can be horizontal, vertical, or diagonal.

Because the pieces are typically not moved or removed once placed, the game can even be played using paper and pencil. While it is often played on a 15×15 grid, historical versions utilized a larger 19×19 board.

To play, two players alternate turns placing stones on the intersections of the grid. Black always takes the first move. The game continues until one player completes a line of five or the board is completely filled. If the board is full and no five-in-a-row exists, the game ends in a draw. In some specific rule sets, a player must form a line of exactly five stones to win. If a player forms a line of six or more stones, it is called an "overline." Under those specific rules, an overline does not count as a victory.

The history of Gomoku is tied to Japan's Edo period during the mid-1700s. Historical records suggest the game spread among the people due to the skill of Kuwanaya Buemon. He was a merchant from the tenth generation of his family who frequented the Nijō family. By the late Edo period, around 1850, the game's popularity led to the publication of instructional books. The earliest verified book on Gomoku was published in 1856. The game eventually reached Britain in the nineteenth century, where it was known as "Go Bang." This name was likely a corruption of "goban," the Japanese word for a Go board.

A major challenge in Gomoku is the significant advantage held by the first player. In unrestricted play, the black player can often force a win. During the 1989 and 1991 World Championships, the "Pro" opening rule was used. This rule required Black to place the first stone in the center. Under these conditions, Black won 67 percent of the games. This high win ratio proved the game was too unbalanced for fair tournament play. To fix this, professional tournaments adopted the Swap2 opening protocol in 2009.

The Swap2 protocol creates a much more balanced competition. In this version, the first player places three stones: two black and one white. The second player then has three choices to ensure fairness. They can choose to play as Black, play as White and place another white stone, or place two more stones of different colors. If they choose the third option, they pass the choice of color back to the first player. This system has successfully leveled the playing field, bringing the first player's win ratio down to approximately 52 percent.

Many distinct variants exist to change the game's complexity. Renju is a popular version that uses extra rules to limit Black's power. It applies the "three and three" and "four and four" rules to Black only. These rules ban moves that create two open rows of three or two rows of four simultaneously. Another variant, Ninuki-renju, introduces "custodial capture." In this version, a player can capture a pair of stones by sandwiching them lengthwise.

Other versions like Pente and Caro offer different ways to balance the game through overlines or specific row requirements.

Gomoku also connects to broader mathematical and theoretical concepts. It is considered a specific type of "m,n,k-game," which is a general category of games played on an m×n board where k stones in a row win. For example, the popular game Connect Four is a variation of this concept. In Gomoku, expert players often engage in "forcing sequences." These are long chains of moves where one player's move forces a specific response from the opponent. Skilled players can accurately read and calculate these sequences, which can last between 20 and 40 moves.