I've long been trying to come up with an elegant, simple set of rules which succeeded in making Go into a naturally finite game, without the need for superko rules. That hypothetical game would no longer be Go, of course, but it should feel as close to Go as possible and preserve most of its virtues.

Till now, my only (published) attempt at this particular task was Paper and Pencil Go, which was interesting but still far from ideal, as making life was too easy.

Now I'm presenting Goncrete, which is a much more balanced game and, hopefully, closer to Go in its play.

GONCRETE

The rules are those of Go, with the following exceptions:

• After each placement, surrounded enemy groups are not removed from the board, but just flipped, i.e. converted to the player's color. Then, the player must remove one stone from as many of the groups just flipped as possible without splitting the newly formed group.
  
• The game ends when both players pass in succession or when one player loses all his stones as a result of a capture.
  
• Suicide is illegal.
  
• Area scoring is used.

Sample positions

Click Here To Show Diagram Code

[go]$$W After White 1...
$$ -----------
$$ | . . . . .
$$ | . . 1 . .
$$ | . O X O .
$$ | . . O . .
$$ | . . . . .[/go]

Click Here To Show Diagram Code

[go]$$B ...the single flipped stone\ncan't be removed, because\nthat would split the new\nWhite group into four groups.
$$ -----------
$$ | . . . . .
$$ | . . O . .
$$ | . O O O .
$$ | . . O . .
$$ | . . . . .[/go]

========================================

Click Here To Show Diagram Code

[go]$$W After White 1...
$$ -------------------
$$ | . . . . . . . . .
$$ | . . O O . O O . .
$$ | . O X X 1 X X O .
$$ | . O O O . O O . .
$$ | . . . . . . . . .[/go]

Click Here To Show Diagram Code

[go]$$B ...four Black stones are flipped. Then...
$$ -------------------
$$ | . . . . . . . . .
$$ | . . O O . O O . .
$$ | . O O O O O O O .
$$ | . O O O . O O . .
$$ | . . . . . . . . .[/go]

Click Here To Show Diagram Code

[go]$$B ...the group on the left allows the removal\nof one stone without splitting the\nnewly formed group, but the one on\nthe right does not. When possible, such removal\nof one stone per group is mandatory.
$$ -------------------
$$ | . . . . . . . . .
$$ | . . O O . O O . .
$$ | . O . O O O O O .
$$ | . O O O . O O . .
$$ | . . . . . . . . .[/go]

==========================================================

Click Here To Show Diagram Code

[go]$$W After White 1...
$$ -------------
$$ | . . . . . .
$$ | . . O 1 . .
$$ | . O X X O .
$$ | . O O X O .
$$ | . . O O . .
$$ | . . . . . .[/go]

Click Here To Show Diagram Code

[go]$$B ...any of the three flipped stones\ncan be removed. In such cases,\nthe result will be exactly the same\nno matter which stone you choose.
$$ -------------
$$ | . . . . . .
$$ | . . O O . .
$$ | . O . O O .
$$ | . O O O O .
$$ | . . O O . .
$$ | . . . . . .[/go]

==========================================

Click Here To Show Diagram Code

[go]$$W White 1 ends the game, as\nall the Black stones are \ncaptured. If the game were\nallowed to continue, an endless\nseries of captures and recaptures\nwould take place. Allowing suicide\nwould cause a similar problem.
$$ ---------
$$ | X X X |
$$ | X X X |
$$ | X 1 O |
$$ ---------[/go]

Click Here To Show Diagram Code

[go]$$B Final position.
$$ ---------
$$ | O O O |
$$ | O . O |
$$ | O O O |
$$ ---------[/go]

What do you think about this Go variant?

_________________
Sum ergo non ero.

Could you show a sample game, maybe 9x9?

Better yet, let's play it.

_________________
Sum ergo non ero.

Looks like the main difference is that you got rid of ko fights entirely and the ko is won by the player of captures first. Which in my book makes the game inferior to go, since ko fights are one of the most interesting aspects of go.
And of course there are some changes to life and death, but I don't think those affect the complexity of the game too much. In particular it's harder to live with a big eye.

_________________
Sanity is for the weak.

Not that it matters in this case, but I think you overfilled after 55 by your rules. It's the minimum number of fills to connect everything, correct? You can do that with 3 stones I think.

Also, here's a "goncrete" puzzle for you:

Click Here To Show Diagram Code

[go]$$B Status of group?
$$ -------------------
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . , . . |
$$ | . . . . . . . . . |
$$ | . . . . , . . . . |
$$ | . . . O O O O . . |
$$ | . . O O X X O O . |
$$ | . . O X . O X O . |
$$ | . . . X O X X . . |
$$ -------------------[/go]

It isn't the minimum number of fills. You must replace the captured stones with stones of your own color. This is called 'flipping'. Then, you must remove one (and only one) stone from as many of the flipped groups as possible, and not "as many stones as possible from every group", as you probably understood.

The rule you suggest makes for a different variant. In fact, it's one of the handful of ideas I have dismissed in my pursuit of a good, naturally finite Go variant. Not that it wouldn't be an interesting variant, but it would be harder to understand, and creating life would be somewhat easier.


In Goncrete, it's dead. If Black captures at E2, he only gets one eye (E1 or F2). That's a good explanatory position!

_________________
Sum ergo non ero.