i'm still flushing out the rules, so maybe you could help.
i'm thinking of making a go variant where either player can play instead of a white or black stone a neutral stone:
the neutral stone cannot be captured, or completely surrounded by a single color.
the neutral stone is not considered connected to a group under any circumstances. (doesn't increase liberties.)
a neutral stone cannot be placed orthogonally next to another neutral stone.
suicide is legal with neutral stones.
super ko rule.

so some examples.

Click Here To Show Diagram Code

[go]$$ a suicide play (before)
$$. O . . . .
$$O X O . . .
$$O X O . . .
$$O . O . . .
$$. O . . . .
----------------[/go]

if it's black's move, he may play a neutral stone at his last liberty to capture his own group. the neutral stone itself is not removed, so white's group has 1 less point of territory.

Click Here To Show Diagram Code

[go]$$ a suicide play (after)
$$. O . . . .
$$O . O . . .
$$O . O . . .
$$O * O . . .
$$. O . . . .
$$. . . . . .
--------------[/go]

whites group its still alive however. black would have to capture one of the two white stones that aren't connected to the two 3 stone groups to kill. the south white stone has 3 current liberties.
note that a neutral stone cannot be placed at the top left corner, as this space is completely surrounded by a single color; nor can white play the spot on top of the neutral stone.

here's a more strategic way to use a neutral stone.

Click Here To Show Diagram Code

[go]$$ an unusual capture (before)
$$. . . X .
$$. O O X .
$$. O X * X
$$. O X . .
$$. . O X .
$$. . O X .
-------------[/go]

white just played the neutral stone. black cannot surround it, so must accept the capture of the two stones on white's next move.

Click Here To Show Diagram Code

[go]$$ an unusual capture (after)
$$. . . X .
$$. O O X .
$$. O . * X
$$. O . O X
$$. . O X .
$$. . O X .
------------[/go]

however, black can now immediately capture back.

hope that makes sense.
--edited for clarity.

Could you use some diagrams?

viewtopic.php?f=5&t=226

EDIT: Thanks - that makes more sense.

Can I take a ko with a neutral stone? If so, I just made an eye.

Click Here To Show Diagram Code

[go]$$B A live group
$$ . . . . . . . . .
$$ . . O O O O O . .
$$ . O O X X X O O .
$$ . O * . X . * O .
$$----------------[/go]

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hmmm, i was thinking yes originally, but after that comment, not sure it should be allowed.
making two eyes would be much easier then.
" a neutral stone cannot be completely surrounded orthogonally by a single color."
so I'd say no.

It might be easier to have the random placement of half a dozen neutral stones at the beginning of the game.

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Hmmm....life and death could get tricky....

Click Here To Show Diagram Code

[go]$$Bc The L group lives?(B3 @ T17, B5 @ Q19)
$$------------
$$. . * . 1 .|
$$O . O X 4 2|
$$. . O X . *|
$$. . O X X .|
$$. . . O O .|
$$. . . . . .|
$$. . . . O .|[/go]

White cannot play both T16 and S17. The Q19/R18/S19 shape acts as an eye as demonstrated above.

Of course....

Click Here To Show Diagram Code

[go]$$Bc W tries harder?(W2 @ S18, B3 @ Q19)
$$------------
$$. . * . 1 .|
$$O . O X * .|
$$. . O X . 4|
$$. . O X X 5|
$$. . . O O 6|
$$. . . . . .|
$$. . . . O .|[/go]

B3 is forced because if W gets to play a neutral stone at R19 the corner is stripped away. B can't play T18 because the neutral stone would mean he could never play S17...after W6, B seems to be in trouble? If B tries t18 it's not even a ko (since B can never play s17), white will capture everything.

Click Here To Show Diagram Code

[go]$$Bc B has no good move (B1, B3=pass) W6 at marked point
$$------------
$$. . * . X 4|
$$O . O X * 2|
$$. . O X 5 W|
$$. . O X X X|
$$. . . O O O|
$$. . . . . .|
$$. . . . O .|[/go]

W6 would be atari, and B cannot capture....maybe the L group still is dead...I'll have to look at this more..

Actually, I was thinking about this some more....

Click Here To Show Diagram Code

[go]$$B a suicide play (after)
$$. O 2 . . .
$$O 1 O . . .
$$O . O . . .
$$O * O . . .
$$. O . . . .
$$. . . . . .
--------------[/go]

As I understand it B1 is alive now? And if W doesn't play a move like 2, black playing a neutral stone here is potentially problematic?

hmmm! i'd have to agree! black's move is a seki move, it can't be killed.

Woaah, those stones would be super-powerful! You could cut almost any loose connection with them. For example, let's look at a common joseki:

Click Here To Show Diagram Code

[go]$$c seems dubious
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . 3 . . . . |
$$ | . . . , . . . . . , . . . . 2 , 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

there might actually be a bad move here now. The punishment:

Click Here To Show Diagram Code

[go]$$c Devastating cut!
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X * . . . |
$$ | . . . , . . . . . , . . . . O , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

followed by a capturing race:

Click Here To Show Diagram Code

[go]$$Bc5 Devastating cut!
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . 4 3 5 6 . . |
$$ | . . . . . . . . . . . . . 2 X * . . . |
$$ | . . . , . . . . . , . . . . O 1 X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

black cannot save those three stones any more now...

If these neutral stones are included in the game, almost any loose connection ceases to work, so you have to play super-duper solidly. Before you know it, a neutral stone can rip your beautiful connection apart. It might actually be an interesting game though

_________________
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When in doubt, play the most aggressive move

Click Here To Show Diagram Code

[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . a X * . . . |
$$ | . . . , . . . . . , . . . 1 O , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

B1 could be problematic for White. or even a calm move at A

i could be wrong, but doesn't your 1 allow white to capture the black stone?

Click Here To Show Diagram Code

[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . 4 3 . . . . |
$$ | . . . . . . . . . . . . . 2 X * . . . |
$$ | . . . , . . . . . , . . . 1 O , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

your second proposal, black A (here b 2) looks better, black is cut but both his groups are stronger than the single white stone

this go variant seems mind-twisting, to a degree i can't say whether i like it or not. interesting for sure

_________________
Spilling gasoline feels good.

I might be wrong, but probably not.

Click Here To Show Diagram Code

[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . 4 3 . . . . |
$$ | . . . . . . . . . . . . . 2 X * . . . |
$$ | . . . , . . . . . , . . . 1 O , X . . |
$$ | . . . . . . . . . . . . . . 5 . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

B5 captures the W stone

Click Here To Show Diagram Code

[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . b . . |
$$ | . . . . . . . . . . . . . 3 X * . . . |
$$ | . . . , . . . . . , . . . 1 O a X . . |
$$ | . . . . . . . . . . . . . . 2 . 4 5 . |
$$ | . . . . . . . . . . . . . . . . . 6 . |[/go]

This could be tricky though, because if white can force black to play 'a' in any variation he can play a living stone at 'b' and black has nothing in the corner (aside from any other threats to capture).

Hey guys,

I figured I'd throw in real quick. I'd actually contemplated an idea somewhat like this. One thing to consider, as someone said, these stones can be crazy powerful. You could, it sounds like, gouge out the eyes of an established live group. Just play your neutral stone at one eye. The group is now (assuming it only has 2 eyes) dead. Might I suggest a (very) limited number of these to be played, or as someone suggested, distribute a few before hand.

Have fun and God bless,
Adam

I think it'd be fun to try a game using these rules. I like the idea of the neutral stone. Anyone want to try?

_________________
Slava Ukraini!

Agreed, but how would players play it if they could only play online? Malkovich game?

_________________
My plan to become an SDK is here.

That's what I had in mind. Probably should have made that clearer lol

_________________
Slava Ukraini!

This idea could be interesting...but I think there's a lot of weird implications to neutral go...One example is this invasion:

Click Here To Show Diagram Code

[go]$$Wc W3 is a neutral stone
$$ --------------
$$ . . . . . . . |
$$ . . . a . 5 . |
$$ . . X 2 * . . |
$$ . . . 1 X b . |
$$ . . . 4 . . . |
$$ . . . . . . . |[/go]

Here is alive, and W will have a follow up at A or B.

If B gets tricky....

Click Here To Show Diagram Code

[go]$$Wc W3 is R17, W5 is Q17
$$ --------------
$$ . . a . b . . |
$$ . . . * . 4 . |
$$ . . X 2 * . . |
$$ . . . 1 X . c |
$$ . . . . . . . |
$$ . . . . . . . |[/go]

prevents the living stone, but after a second neutral stone one of A, B or C will live (because B must leave a point around each neutral stone open....

B gets really tricky....

Click Here To Show Diagram Code

[go]$$Wc W3 is R17, B4 is S18
$$ --------------
$$ . . . . . . . |
$$ . . 6 5 . * . |
$$ . . X 2 * . . |
$$ . . . 1 X 7 . |
$$ . . 9 . 8 . . |
$$ . . . . . . . |[/go]

B cannot capture both and ......my brain hurts just trying to wrap my head around this...

Edit - my wires are totally crossed in my last diagram didn't make sense, I've since changed it (=

I can see why you'd say that lol. Still, I think it'd be fun to try, at least. Maybe on 9x9 and see how that goes.

_________________
Slava Ukraini!

I'd be up for a 9x9 game, if we can get the rules straightened out.

_________________
My plan to become an SDK is here.

I really think that the neutral stones should be a limited resource. Perhaps you might want to settle on a number of neutral stones you each get at the beginning of the game, and that's it.

For a 9x9 game, I like the idea of giving 2 neutral stones each. It's such a small board that locally a neutral stone can be devastating to the entire game. For 19x19, something like 6 neutral stones each would be a good place to start, I think. This might actually be too many neutral stones in both cases, but experimentation is required.