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        Team Games >> 2009 One vs TheMob >> Move 38
        
(Message started by: Nombril on May 21st, 2010, 6:23pm)
Title: Move 38
Post by Nombril on May 21st, 2010, 6:23pm
37s:  rg6e hg5n Rg4n ef4e
Title: Re: Move 38
Post by Nombril on May 21st, 2010, 6:30pm
It seems we can have time to take the c5 dog...something along the lines of
38g rb6w Db5n dc5n dc6x Ed5w
38s Hg3s eg4s Hg2s eg3s
39g Ec5e dd4s Ed5s Rc4n
39s ra4e ca5e Rc5s cb5e
40g dd3w dc3x Ed4s Ed3e Ca3e

This is just a first glance - there is probably a better defense.
Title: Re: Move 38
Post by lostcalpolydude on May 21st, 2010, 7:47pm
I was thinking

38s Hg3w eg4s rh4s ? (maybe rb8e as a defensive step)

but I see that working out well for us still.  I think he has to take the g7 dog and bring his horse over to defend around the c6 trap.
Title: Re: Move 38
Post by Hippo on May 22nd, 2010, 5:30am
I have no plan window available now, but I like our position. We can choose which dog to change. c5 is attaccking move d4 is defensive one. As I remember c5 could be OK.
Title: Re: Move 38
Post by chessandgo on May 22nd, 2010, 6:03am

on 05/21/10 at 18:30:32, Nombril wrote:
It seems we can have time to take the c5 dog...something along the lines of
38g rb6w Db5n dc5n dc6x Ed5w



on 05/21/10 at 19:47:13, lostcalpolydude wrote:
I was thinking

38s Hg3w eg4s rh4s ? (maybe rb8e as a defensive step)


Yeah definitely this, Nombril's 38s allows us to advance the Rc4 to c6 and goal on next move. I don't think silver can capture anything on f6 for the same reason. I don't think sacrificing the Hf3 on 39g works:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s rh4s rb8e
39g Cc2n Ec5e Rc4n Cc3x Rf2e Hf3x
39s ca5e ra6s Rc5s cb5e
40g cc5n cc6x Ed5w Rc4w Rb4n
40s Rg2w eg3s ra7e

but I can smell blood too :) I would be surprised if we don't find a forced (or at least intuitively forced) goal in this thread.

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s rh4s rb8e
39g Hf3n Rf2e Hf4e Hg4e

does already look very good (note that silver can't capture the Dg7 without allowing goal).

Also 39g Rd2e Re2n Rf2e Ec5e seems to pretty much kill the game (I guess the resulting position should be a goal in 3/4 or 5 maybe).
Title: Re: Move 38
Post by jdb on May 22nd, 2010, 6:11am

on 05/21/10 at 19:47:13, lostcalpolydude wrote:
I was thinking

38s Hg3w eg4s rh4s ? (maybe rb8e as a defensive step)

but I see that working out well for us still.  I think he has to take the g7 dog and bring his horse over to defend around the c6 trap.


This move looks stronger. We will need to check this out fully to be sure the c5 dog can be taken.
Title: Re: Move 38
Post by Hippo on May 22nd, 2010, 1:02pm

on 05/22/10 at 06:03:48, chessandgo wrote:
38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s rh4s rb8e
39g Rd2e Re2n Rf2e Ec5e seems to pretty much kill the game (I guess the resulting position should be a goal in 3/4 or 5 maybe).


I like this variant +1 for taking c5 dog.
I would be surprised if we will not win till 42g.
Title: Re: Move 38
Post by RonWeasley on May 22nd, 2010, 5:15pm
After taking the c5 dog, I'm worried about

38s Hg3w eg4s hh4s eg3s

Defending, 39g Hf3e Ec5e Ed5e Ee5e (maybe there's better way)

Then 39s rh6s rh5s Rg5s hg6s

Can't take the h3 rabbit with the horse because 40s eg2s Rh2w rh4s rh3s

The only other 40g stopping goal is Hg3w rh3w with two other steps.  The other two steps protect the horse (and goal).  Then silver does 41s eg2s Rh2w rh4s rh3s anyway.

So please help show this does not lose.  Otherwise, I say take the d4 dog instead.
Title: Re: Move 38
Post by Nombril on May 22nd, 2010, 7:04pm
Ron, how about:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s rh4s eg3s
39g Ec5e Hf3e Cc2s Ca3e
39s rh6s rh5s ra4e ca5e
40g Cc1e Cd1e Ce1e Cf1e

Our b3 cat can step north to unfreeze our rabbit, and having our extra cat on goal defense behind silver's elephant should keep things slow enough for us to goal, right?

At this point, I looked at pushing the f2 rabbit north, but we can put the d2 rabbit to f2 in two steps, while unfreezing our c4 rabbit.  I don't see what other pieces can come help the attack.

I certainly expect that Fritz sees our threat, and he has continued his attack because either:
a.  we are missing something
or
b.  he hopes we miss something
Title: Re: Move 38
Post by chessandgo on May 23rd, 2010, 1:17am
aha, nice. I can't find a forced goal after

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s
39g Cc2n Ec5e Rc4n Cc3x Hf3e
39s ca5e ra6s Rc5s cb5e

and

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s
39g Cc2n Hf3e Ec5w Rc4n Cc3x
39s ra7e rb7e dd4n dd5n

seems to defend as well for silver. And:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s
39g Hf3n Hf4e Rg5e Hg4s
39s Hg3n eg2n Hg4n eg3n
40g Rf2e Cc2n Ec5e Rc4n Cc3x
40s ca5e ra6s Rc5s cb5e

or

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s
39g Hf3n Hf4e Rg5e Hg4s
39s Hg3n eg2n Hg4n eg3n
40g Cc2n Rd2n Rf2e Ec5e
40s eg4w rh3w rg3w rb8e

are not so clear either.

Hum.

Maybe quad's analysis would be helpful here (not sure whether aaaa still reads the Mob forum)?
Title: Re: Move 38
Post by chessandgo on May 23rd, 2010, 1:44am

on 05/22/10 at 19:04:50, Nombril wrote:
Ron, how about:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s rh4s eg3s
39g Ec5e Hf3e Cc2s Ca3e
39s rh6s rh5s ra4e ca5e
40g Cc1e Cd1e Ce1e Cf1e

Our b3 cat can step north to unfreeze our rabbit, and having our extra cat on goal defense behind silver's elephant should keep things slow enough for us to goal, right?

At this point, I looked at pushing the f2 rabbit north, but we can put the d2 rabbit to f2 in two steps, while unfreezing our c4 rabbit.  I don't see what other pieces can come help the attack.


This does look good. I guess I was too optimistic about forcing a goal, but here we have two extra pieces and a strong goal attack. I don't think silver can't get anything going on the h-file before we goal in the west.
Title: Re: Move 38
Post by jdb on May 23rd, 2010, 5:51am
I did some analysis with clueless.

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s
39g Cc2n Ec5e Rc4n Cc3x Hf3e
39s ca5e ra6s Rc5s cb5e

40g dd4s Ed5s dd3w dc3x Ed4s
40s ra4e rb4s rh8s rh5s
And goal the next move for silver.

Other 40g moves look very complicated.
40g Rd2e Re2n Ca3e Db6s is what clueless likes so far.

I think attacking on 39g in this line will make the game very complicated.
Title: Re: Move 38
Post by Hippo on May 23rd, 2010, 6:33am
Yes, I don't like the cat sacrifice at 39g.
Having the cat at g1 is much better plan.
I cannot see Fritzlein further counterattacks or defences.

(38g rb6w Db5n dc5n dc6x Ed5w
38s Hg3w eg4s rh4s eg3s
39g Hf3e Ca3e Cc2s Ec5e
39s rh6s rh5s rb8e ca5e
40g Cc1e Cd1e Ce1e Cf1e
40s Rf2n eg2w ef2e ra6s
41g Rd2ee x x we have more options, but not immediate goal)

I am still voting +1 for capturing the c5 dog (with ra6) ... but this needs more than 42 turns :(.

Capturing d4 dog would give Fritzlein time to capture our dog and consolidate. In recommended variant our cat advantage would apply as both our cats start participating.
Title: Re: Move 38
Post by jdb on May 23rd, 2010, 7:31am
For the following line:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s

On 38g, instead of rb6w, rb6n is possible.

On 38s, The elephant can stop on g3. This allows silver a step elsewhere which will alter the tactics considerably.

Just a couple things to keep in mind while looking at this move.
Title: Re: Move 38
Post by Hippo on May 23rd, 2010, 7:47am

on 05/23/10 at 07:31:47, jdb wrote:
For the following line:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s

On 38g, instead of rb6w, rb6n is possible.

On 38s, The elephant can stop on g3. This allows silver a step elsewhere which will alter the tactics considerably.

Just a couple things to keep in mind while looking at this move.

It seems to me eg2 step is essential as it makes goal in 1 threat. Otherwise we could probably spent all 4 our steps attacking. And with rabbit at c6 rather than c5 it would be much difficult to defend.

Oops ... I had to look to board at first ... you are right
Title: Re: Move 38
Post by RonWeasley on May 23rd, 2010, 9:56am
Nombril's cat defending at g1 seems to address my worry about taking the c5 dog.  I like our position after Hippo's line.

on 05/23/10 at 07:31:47, jdb wrote:
For the following line:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s

On 38g, instead of rb6w, rb6n is possible.

On 38s, The elephant can stop on g3. This allows silver a step elsewhere which will alter the tactics considerably.

Just a couple things to keep in mind while looking at this move.

I prefer rb6w over rb6n because that rabbit is not one step away from the c-file, blocking our goal threat.

If the silver e stops on g3 (Hg3w eg4s rh4s rh6s), I think Hf3w Rf2e Rd2e Re2e blocks silver (I can't find any other move that does).  And then gold has a free E to escort the rabbit up the c-file.  If silver pushes to g2, gold can bracket the silver e with the help of the c2 C.

So I would be ready to voice vote for taking the c5 dog, pushing the b6 rabbit west.
Title: Re: Move 38
Post by chessandgo on May 23rd, 2010, 2:13pm

on 05/23/10 at 05:51:40, jdb wrote:
I did some analysis with clueless.

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s
39g Cc2n Ec5e Rc4n Cc3x Hf3e
39s ca5e ra6s Rc5s cb5e

40g dd4s Ed5s dd3w dc3x Ed4s
40s ra4e rb4s rh8s rh5s
And goal the next move for silver.

Other 40g moves look very complicated.
40g Rd2e Re2n Ca3e Db6s is what clueless likes so far.

I think attacking on 39g in this line will make the game very complicated.


Cool, thanks for running clueless jdb!

After 40g Rd2e Re2n Ca3e Db6s though, isn't 40s rh6ss Rg5s hg6s, as Ron proposed in another variant, a forced goal for silver?
Title: Re: Move 38
Post by chessandgo on May 23rd, 2010, 2:19pm

on 05/23/10 at 07:31:47, jdb wrote:
For the following line:

38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s eg3s rh4s

On 38s, The elephant can stop on g3. This allows silver a step elsewhere which will alter the tactics considerably.

Just a couple things to keep in mind while looking at this move.




on 05/22/10 at 06:03:48, chessandgo wrote:
38g dc5n Ed5w rb6w dc6x Db5n
38s Hg3w eg4s rh4s rb8e
39g Hf3n Rf2e Hf4e Hg4e

does already look very good (note that silver can't capture the Dg7 without allowing goal).

Also 39g Rd2e Re2n Rf2e Ec5e seems to pretty much kill the game (I guess the resulting position should be a goal in 3/4 or 5 maybe).


Are the above moves not convincing, or do you have other 4th steps for 38s in mind?
Title: Re: Move 38
Post by jdb on May 23rd, 2010, 3:03pm

on 05/23/10 at 14:19:11, chessandgo wrote:
Are the above moves not convincing, or do you have other 4th steps for 38s in mind?


I am semi-convinced. The main line given below, looks good to clueless.


Quote:
(38g rb6w Db5n dc5n dc6x Ed5w
38s Hg3w eg4s rh4s eg3s
39g Hf3e Ca3e Cc2s Ec5e
39s rh6s rh5s rb8e ca5e
40g Cc1e Cd1e Ce1e Cf1e
40s Rf2n eg2w ef2e ra6s
41g Rd2ee x x we have more options, but not immediate goal)


My concern is that move 40g is totally forced. This gives silver 6 (!) steps to work with, the last two steps of 39s and all 4 steps of 40s. I would feel more comfortable with the move if, some of these plans were discussed.

For example, silver can do something like,

ra4s ca5s, ca4e Rc4s cb4e dd4s

And silver's goal threats are more pressing than gold's.
Title: Re: Move 38
Post by Nombril on May 23rd, 2010, 5:25pm

on 05/23/10 at 15:03:15, jdb wrote:
ra4s ca5s, ca4e Rc4s cb4e dd4s


I think this would be great for us,
41g Ed5e Ee5e Rg5e Ef5e
looks like goal in 1 for gold?

But I do agree with your concern about the 6 "free" steps.  We don't have the greatest record in correctly predicting Fritz's moves!  I'm glad we seem to have more people looking at this move than the previous few.
Title: Re: Move 38
Post by Nombril on May 23rd, 2010, 6:05pm
Since we have a few days still... should we take a look at capturing the d4 dog?

Or even 38g Rd2e Re2n Re3n Rh2n?
Title: Re: Move 38
Post by chessandgo on May 24th, 2010, 12:02am

on 05/23/10 at 17:25:13, Nombril wrote:
I think this would be great for us,
41g Ed5e Ee5e Rg5e Ef5e
looks like goal in 1 for gold?


I agree with this
Title: Re: Move 38
Post by chessandgo on May 24th, 2010, 12:06am
I'm not sure taking the d4 dog is really attractive. Silver still have the same attacking option, the difference is essentially that gold doesnt' have goal prospects in the west (unless we want to use our Elephant to defend on the east, in which case we're going to lose at least DR for d.
Title: Re: Move 38
Post by jdb on May 24th, 2010, 4:53am
I did some more looking with clueless. I'm now convinced its ok to take the dog.
Title: Re: Move 38
Post by arimaa_master on May 24th, 2010, 5:00am
+1 for 38g rb6w Db5n dc5n dc6x Ed5w
Title: Re: Move 38
Post by RonWeasley on May 24th, 2010, 5:21am
If I read this correctly, we have C&G, jdb, Hippo, Nombril, a_m, and me all voice voting for capturing the c5 dog while pushing rb6w.  That's enough to make the move.  I'll wait a few hours in case someone really thinks we should discuss this more.
Title: Re: Move 38
Post by Hippo on May 24th, 2010, 7:31am
I am still for, but seems jdb needs some more time.
Title: Re: Move 38
Post by jdb on May 24th, 2010, 8:26am

on 05/24/10 at 05:21:32, RonWeasley wrote:
If I read this correctly, we have C&G, jdb, Hippo, Nombril, a_m, and me all voice voting for capturing the c5 dog while pushing rb6w.  That's enough to make the move.  I'll wait a few hours in case someone really thinks we should discuss this more.


I will vote for this move.
Title: Re: Move 38
Post by RonWeasley on May 24th, 2010, 3:48pm
OK.  This is a consensus and I make the move.

The game is in a critical state now.  If our analysis is right, we should soon see gold with a more obvious advantage.  If we're wrong, silver will goal quickly.  There are at least two lines where we think we have only one or two moves that defend goal and lead to victory.  This is much like top level chess games where a single brilliant reply turns a win into a blunder.  So in that respect, I think we are seeing arimaa getting more mature.


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