European Championship, European Open Championship, Week-end tournament, side tournaments
Simplified Ing Rules and Japanese fill-in counting
- Komi: 7.5 for even games.
- Move: A move is either a play or a pass.
- Pass: When passing, a player gives one stone from his bowl to the opponent as a prisoner.
- Suicide: A play may remove one's own stones.
- No repetition: A play may not recreate a previous position.
- Stop: Alternate moving stops with two successive passes.
- Agreement: After the first stop, the players may make an agreement about all regions that shall be removed:
- If they agree, they remove those regions and add them to their prisoners. Then they proceed to the eventual white extra pass and determine the result.
- If they disagree, they resume alternate moving. After the second stop, they immediately proceed to the eventual white extra pass and determine the result.
- White extra pass: After the agreement or the second stop, if Black made the last pass, then White makes an extra pass and gives a pass stone from his bowl to Black, so that both players will have made an equal number of moves during the game.
- Determining the result: The Chinese style Area Scoring (a player's territory plus his stones on the board) is used. The Area Score of a game is determined by means of Japanese Counting. This is enabled by the pass stones and the White passes last rule; all such pass stones have become part of the prisoners and are now counted. Japanese Counting first fills in prisoners as far as possible, then rearranges remaining territories conveniently, then compares remaining territories and any possibly remaining excess prisoners that could not be filled in and the komi. Note that, in sekis, empty intersections surrounded by both black and white stones are not filled during the counting at all.
- Strategy: Correct strategy is that of Area Scoring:
- Each mutual dame is worth 1 point: Play on to fill it!
- Each one-sided dame in a scarce seki is worth 1 point for the player who can and does fill it.
- The last endgame ko is worth 2 points if the opponent can still fill a dame in between.
- The last endgame ko is worth 4 points if all dame are already filled. If a player has a great excess of ko threats, then he might succeed in postponing filling the ko until the opponent cannot even use dame as ko threats any longer.
- Sekis can have territory. This is relevant in the scarce asymmetrical sekis, where the players exclusively surround different numbers of empty intersections.
- Handicap games: The placement of the handicap stones is free. In order to determine the Area Score by means of Japanese Counting, the komi in handicap games is set to N-0.5, where N is the number of handicap stones.