(there exist regional variants, I here relate the rules used in international tournaments and in serious online games)
Play is like tic-tac-toe except…
Instead of needing exactly 3-in-a-row to win, you need exactly 5-in-a-row to win (6-plus-in-a-row is ignored)
Instead of playing on a 3x3 board of spaces, you play on a 15x15 board of intersections
A filled board is still a draw if noöne has won yet, but given the larger board players may agree to a draw rather than playing it out
Instead of choosing one player to go first and taking turns, a modified pie rule is used (see below)
Pie Rules
Swap-2 is the pie rule officially used in Tournaments, and it is the most balanced option. Long Pro, which has been used historically, is given despite being less balanced as it may be a good option for younger players or players who might not have enough interest in the game (yet) to get through an explanation of Swap-2
Swap-2 (official, most interesting, and most balanced)
Slicer places 3 stones (2 black, 1 white)
Chooser may either
a. Decide to play black (game starts, it’s white’s turn)
b. Decide to play white (game starts, it’s white’s turn)
c. Place 2 more stones (1 white, 1 black) for a total of 5 stones on the board, and Slicer must choose which color to play (then the game starts, it’s white’s turn)
Long Pro (simple; good for younger children or complete beginners)
Black plays move 1 on tengen
White plays move 2 anywhere
Black plays move 3 anywhere except the center 7x7 square (ie, black must play on the 4th line or below)
The game continues on as normal with no further placement restrictions (there is no swapping of colors in Long Pro)
Edward Lasker was instrumental in developing Go in the U.S., and together with Karl Davis Robinson and Lee Hartman founded the American Go Association.
I’ve long been wondering what board-size would be roughly-fair for
No opening protocol: instead, if the board fills up with neither player
having gotten a winning 5-in-a-row, then the second player wins.
.
Also, I had not seen the exactly 5 aspect before, and am now wondering,
Is there a known example of zugzwang or proof that there’s no zugzwang?
.
(The exactly 5 part means having an extra stone
on the board can be harmful to that stone’s player.)
Gomoku has bit more complex rules to avoid the advantage to start the game as just being “5 in a row”. I was never enough interested to learn those rules.
(from Lk on the Gomoku Club Discord Server; all 1st person references to follow are in reference to him)
All ways to win without opening protocol are known and can be learned = for my POV there’s no such thing as “board-size roughly-fair for”
It’s either win or lose (using hocpath’s rules)
Anyway
32 moves is the longest possible win by RAPFI (and good hardware) if played correctly
So maybe something like 7x7 or more likely 8x8 would “complicate” the situation… But nowadays… It’s just countable.
zugzwang → hard question
We have 3 terms
Win
Not win
Lose
zugzwang is about losing cause of playing…
You can have a situation when your opponent has a VCT, you would have a VCF created by defending him but you can’t play it beause he forced you (by playing x°°°) into the “overhang” rule
So this situation might be a zugzwang.
But you could argue that the “excess” stone isn’t causing you loss, but just isn’t helping to win in a certain situation… Which is something every stone sometimes does.
Taking it this way you lost because of you not seeing forward enough / not adapting well to a given situation
Which leads to… What is a zugzwang?
Is it a situation when you know you will lose (cause the game has certain rules you have to follow) and you don’t want to face it?
If so, every loss has a zugzwang.
Is it a situation when having the possibility to “pass” would be better for you than playing?
If so, I am not sure there can be a zugzwang.
What you play can make some of your stones useless, but not “dangerous”.
The only way your opponent can force you to play “overhang” stone is by directly threatening you… And that’s not a situation when you would like not to play… The fact that you allowed him to threaten you is a skill issue.
