Cham Gonu

Rules (as written in the source)

• Players take turns placing their twelve pieces one at a time on the intersections.
• When three of your pieces stand in a straight line, horizontally, vertically or diagonally, you call "kkon" and remove an opponent's piece. The intersection where the piece was removed is marked with a peg so that no more pieces can be placed there.
• Once all twelve pieces are placed, the pegs are removed and pieces move one point at a time. Making three in a line again, you call "kkon" and remove an opponent's piece.
• You win when the opponent has only two pieces left on the board.

The rule sentences follow the gonu guide on the Ministry of Culture, Sports and Tourism children's site, and the board shape is copied from the fifteen diagrams in the same source. Four things the source does not say are our reading: the player who makes kkon chooses which opponent's piece to remove, kkon removes a piece in the moving phase too, a side that cannot move loses, and if there is no opponent's piece to remove the turn simply passes.

Ministry of Culture, Sports and Tourism children's site, gonu guide (Korean)

Notes from playing (our reading, not the source)

The notes below follow from the rules and are our own summary. They are not in the source text.

• The placing phase decides the board. Positions harden before all twelve pieces are down. Take the intersections that several lines pass through first, and one move can threaten several kkon.
• A peg kills a point. Nobody can place on a removed point, so removing a piece from a line the opponent was building blocks that whole line. Keep this in mind when choosing which piece to remove.
• Two in a line makes your next move stronger. With two of yours on a line, the opponent has to block it instead of building their own position. Spread pairs across several lines.
• The moving phase is a different calculation. The pegs are gone and pieces move one point at a time, so the side that can open and close a kkon repeatedly, removing a piece each time, has the edge.

How it differs from the other gonu games

Of the five games, Cham Gonu has the most pieces and the largest board. A placing phase with twelve pieces flows into a moving phase, so one game holds two games of different character.

Neojul Gonu and Jadongcha Gonu are moving games from the start, so the fight begins with the first move. Hobak Gonu has no capture at all; you win only by trapping. Umul Gonu is the smallest and ends within a few moves.

If you are new, get a feel for Umul Gonu first and then come to Cham Gonu. You have to plan your placements ahead, so this is the game of the five that makes you think the longest.