Go

Objective

The objective of Go is to control more of the board than your opponent by surrounding empty space with your stones.

Players take turns placing stones of their colour. Each empty intersection you completely enclose counts as your territory. When the game ends, the player with the most territory — plus any stones they have captured — wins.

You do not need to fill the whole board. A small, securely surrounded area is worth more than a large, leaky one.

Board and Setup

Go on Playboard is played on a 9×9 board. Stones are placed on the intersections where the lines cross — not inside the squares — which gives 81 playable points.

Every game starts the same way:

• The board begins completely empty
• Black always moves first
• White is compensated for moving second with a komi of 6.5 points added to White's score

The empty starting board means both players shape the game entirely with their own moves. There is no fixed opening position to memorise.

Placing Stones

On your turn, place one stone of your colour on any empty intersection. Black plays first, then players alternate turns.

A few rules govern where you may play:

• You may place a stone on any empty intersection, as long as the move is legal
• Once placed, a stone never moves to another point
• A stone is only removed from the board if it is captured

Because stones stay where you put them, every move is a permanent commitment. Think about how a stone works with the ones already on the board before you place it.

Liberties and Capture

Every stone needs liberties to stay on the board. A liberty is an empty intersection directly next to the stone — up, down, left, or right (never diagonally).

Stones of the same colour that touch along these lines form a group, and the group shares all of its liberties. A group survives as long as it has at least one liberty.

When a group's last liberty is filled by enemy stones, the whole group is captured and removed from the board. Each captured stone becomes a prisoner that counts towards the capturing player's score.

Example: Black captures a White stone

The lone White stone on E5 had only one liberty left at E4. When Black plays E4, the White stone has no liberties remaining and is captured — Black scores one prisoner.

Illegal Moves

Almost every empty intersection is a legal move, but two rules forbid certain placements.

Suicide

You cannot place a stone that would have no liberties — unless that same move captures enemy stones first. If your stone (and its group) would be left with zero liberties and nothing is captured, the move is illegal.

In short: a move that only kills your own stones is not allowed.

Ko

The ko rule prevents an endless loop of capture and recapture.

When you capture a single stone, your opponent may not immediately recapture if doing so would recreate the exact board position from one move earlier. They must play somewhere else first; after that the point becomes available again.

Example: a ko shape

Black has just played E5, capturing a single White stone that stood there. White would love to retake at that point immediately — but the ko rule forbids it, because that would rebuild the previous position. White must play elsewhere for one turn first.

Passing and Ending the Game

Instead of placing a stone, you may pass your turn at any time. Passing is a normal move — you usually pass when every remaining point would only help your opponent.

The game ends when both players pass in a row. Two consecutive passes signal that neither side wants to add stones, and the board is then scored.

Before counting, any dead stones — stones trapped inside the opponent's territory with no realistic way to survive — are removed automatically and counted as prisoners. You do not have to capture them by hand; resolving dead stones is handled for you when the game ends.

Territory and Scoring

Playboard uses Japanese (territory) scoring. Each player's score is the sum of two things:

• Territory — every empty intersection completely surrounded by only their stones
• Prisoners — every enemy stone they have captured, plus any dead stones removed at the end

White then adds a komi of 6.5 points to compensate for Black playing first. Because komi is a half-point, the game can never end in a tie — there is always a winner.

Example: a finished, scored board

Black's wall runs down the C-file and White's runs down the G-file. Black surrounds the empty territory behind its wall, White surrounds the territory behind its own. Add each player's enclosed points to their prisoners, give White the 6.5 komi, and the higher total wins.

Strategy Tips for 9×9 Go

The small 9×9 board rewards a few clear habits:

• Take the corners and sides first. Stones near the edge need fewer moves to enclose territory than stones stranded in the centre.
• Keep your stones connected. Linked groups share liberties and are far harder to capture than scattered single stones.
• Make two eyes to stay alive. A group with two separate enclosed empty points can never be captured — this is the most important survival idea in Go.
• Don't fill your own territory. Every stone you place inside your own area is a wasted move that shrinks your score.
• Know when to pass. If no move gains points and every play just hands liberties to your opponent, passing is the strongest choice.
• Count before you fight. Compare your secure territory to your opponent's; if you are already ahead, play safely instead of starting risky battles.