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        Team Games >> 2009 One vs TheMob >> 2015 Move 20g
        
(Message started by: deep_blue on Apr 14th, 2016, 9:48am)
Title: 2015 Move 20g
Post by deep_blue on Apr 14th, 2016, 9:48am
Sharp played 19s Rc5s hc6s re8w dd6w:
http://arimaa.com/arimaa/notconv/old/boardimg.php?orient=n&size=300&imgtype=jpeg&ranks=r1rr/rrMc1r/Hmd3cr/REhDd1Rr/2Re2h/6H/1RRCDCR/5R1R
Title: Re: 2015 Move 20g
Post by aaaa on Apr 14th, 2016, 4:16pm
20g Eb5s mb6s Eb4s mb5s should obviously be considered here.
Title: Re: 2015 Move 20g
Post by deep_blue on Apr 14th, 2016, 5:48pm
What that 20g Eb5s mb6s Eb4s mb5s gets answered by simply 20s Rc4s ed4w mb4n mb5n ?
I am not sure what we accomplished. The Rc3 is maybe a little bit better placed but what is our E doing on b3?!
I don't see a good move for use though. We could try 20g Eb5s hc5w Rc4n Eb4e to threaten the silver horse at some point but that doesn't look great either.
Title: Re: 2015 Move 20g
Post by aaaa on Apr 15th, 2016, 3:43pm

on 04/14/16 at 17:48:07, deep_blue wrote:
What that 20g Eb5s mb6s Eb4s mb5s gets answered by simply 20s Rc4s ed4w mb4n mb5n ?
I am not sure what we accomplished. The Rc3 is maybe a little bit better placed but what is our E doing on b3?!
I don't see a good move for use though. We could try 20g Eb5s hc5w Rc4n Eb4e to threaten the silver horse at some point but that doesn't look great either.

You're right. I had this false idea Gold could reply by centralizing the elephant at Silver's expense.
I don't see anything better than your move. For a different plan, one could consider putting a rabbit on a4 to threaten Eb5s mb6s Ha6e Ra5n, but even that isn't much of a threat.
If the decision is made to finally throw in the towel, I, for one, wouldn't object too much to it.
Title: Re: 2015 Move 20g
Post by Hippo on Apr 15th, 2016, 3:59pm
I thought about Rb2-b3, Rc4-b4. Or Rb2-c3, Rc4-a4.
Expecting hd5 Dd6 ec5 in reply (in both cases).

Or may be rather ec4 dc5 De6 he5 in the latter.

I cannot see any way to save our dog or get some compensation for it.
Title: Re: 2015 Move 20g
Post by half_integer on Apr 15th, 2016, 8:10pm
I am also having trouble coming up with moves, but perhaps this:

20g Eb4:Mb5 Mb7:Rb6

If silver moves back to position such as
20s Dd6 Rc6 Mb6 X (De6?)
then we can unhostage the horse with
21g Mc7:Rb7 Ha7 X (Eb5?)

Silver can escape in other ways, however this frees our horse, unless he uses Ma5:Ra4 which puts his camel in a poor position.

Is there another silver response which is much worse for us?

Edit:

It looks like the 20s above modified to Dc7 Rc6 Mb6 X (De6?) would be a Pyrrhic victory for us, with the horse freed but camel and horse trapped in the corner.  However, we could do pull-and-replace on the camel at b6 (with either response) so perhaps this still improves our position.  It at least gives us greater control over his camel.  He could block pull-and-replace with a 4th step Hb5, but then we're tying up more of his pieces defending this maneuver; we could follow up with Ec4 Rcb4 threatening to keep his pieces in the West too.

I also found 20s Rc7 Rc8 H:.Dd6 which blockades the camel, but we might get some benefit from flipping the camel in this line.  (Interesting how there is false protection after 20s but we can't execute it.  However, this becomes a latent threat if we make b5 empty later.)

I'm still not sure these outcomes are worse than from the other available moves.  At least we change the situation to a less static one.
Title: Re: 2015 Move 20g
Post by deep_blue on Apr 16th, 2016, 8:24am
I don't think I like that move. You said that silver camel is misplaced on a5 but e.g. 20s Ra5s mb5w cd7w rd8s I don't think the ma5 is a problem for silver. And then it's not clear for me how we as gold proceed. Our rabbits on a4 and c4 are sort of annoying for our E.
Title: Re: 2015 Move 20g
Post by Hufflepup on Apr 16th, 2016, 1:02pm
What about 20g: Eb5s mb6s Ha6e ra7s This would allow us to get our hostaged horse out of such an awkward position.

If silver pushed the our horse into the trap one possibe follow up would be 21g: Cd2n De2n Cd3w Eb4n in preparation for getting our rabbit out of the way so we can make some kind of threat against the silver horse. We could do something similar if the horse was pushed to b7 instead.

Alternatively we could play 20g: De2n Cd2n Cd3w Rc4w immediately. This would expose the Cat on the trap to capture, but I can't see a way for silver to take it this turn without taking a bigger loss e.g.

20g: De2n Cd2n Cd3w Rc4w
20s: ed4s ed3s ed2n Rc2e
21g: Rb4w hc5s Eb5e Dd5n

Looks good for us.
Title: Re: 2015 Move 20g
Post by Hufflepup on Apr 16th, 2016, 1:37pm

Quote:
20g Eb4:Mb5 Mb7:Rb6

If silver moves back to position such as  
20s Dd6 Rc6 Mb6 X (De6?)
then we can unhostage the horse with
21g Mc7:Rb7 Ha7 X (Eb5?)

Silver can escape in other ways, however this frees our horse, unless he uses Ma5:Ra4 which puts his camel in a poor position.

Is there another silver response which is much worse for us?


What about 20s: Ra5s mb5w rb6s dc6w

I can't see how we would be able to threaten either the silver horse or camel from this position, our elephant would be highly decentralised, and the silver a5 rabbit would become very dangerous if we attempted to move the elephant. Meanwhile silver can capture our dog and rabbit.
Title: Re: 2015 Move 20g
Post by Hippo on Apr 16th, 2016, 1:44pm
For moves ending with Rb4 reply like ec5 hd5 De6 look good for silver.

... but it does not mean we have a better option ...

What about rb8 Mb7 without camel pull?

What with the remaining steps? De3, Cd3?
Title: Re: 2015 Move 20g
Post by half_integer on Apr 16th, 2016, 2:44pm
With M:Rb8 our camel is easily blockaded.  Effectively both our camel and horse would still be frozen, and we have no immediate threat against the silver horse or camel.  This seems too favorable to silver to me.
Title: Re: 2015 Move 20g
Post by Hippo on Apr 16th, 2016, 3:50pm
It seems to me pull and replace at b6 could be fine (if silver spends time blocking the camel) ... with possible future camel flip
Title: Re: 2015 Move 20g
Post by Hufflepup on Apr 16th, 2016, 5:13pm

Quote:
For moves ending with Rb4 reply like ec5 hd5 De6 look good for silver.


Do you mean 20s: Dd5n hc5e ed4w ec4n ? That looks like a very strong response. I can't see how we could make any kind of response quick enough to gain any compensation for the dog and rabbit, so I consider this proposal to be refuted.

I agree with half_integer about M:Rb8. This leaves continuing to make some kind of threat against the camel which brings me back to 20g: De2n Cd2n Cd3w Rc4w.

Whilst sivler can retreat the camel to b6 it  looks very difficult to reestablish the horse hostage from that position, so we make some kind of strategic gain. Silver also couldn't make any progress on capturing our dog/rabbit on 20s without allowing us to flip his camel into a very exposed position.
Title: Re: 2015 Move 20g
Post by Lion on Apr 16th, 2016, 9:40pm
What about getting a rabbit to a4 (threatening the camel pull + horse and rabbit advance)?
Title: Re: 2015 Move 20g
Post by Hippo on Apr 17th, 2016, 4:41am

on 04/16/16 at 21:40:55, Lion wrote:
What about getting a rabbit to a4 (threatening the camel pull + horse and rabbit advance)?


It was my 2nd proposal ... see my 1st post
(and aaaa's one post earlier).
Title: Re: 2015 Move 20g
Post by Heyckie on Apr 17th, 2016, 11:25am
Please, could you give an actual 20s refuting 20g rb7n Mc7w De2n Cd2n ? It seems to me we get our M to b6 ( 21g Eb5s mb6s Mb7s xxxx ) no matter what Silver plays. Dd5 and Rg5 can't be saved anyway. 20g Eb5s mb6s Ha6e ra7s is another attacking move I like here.
Title: Re: 2015 Move 20g
Post by Hufflepup on Apr 17th, 2016, 12:51pm

Quote:
Please, could you give an actual 20s refuting 20g rb7n Mc7w De2n Cd2n ? It seems to me we get our M to b6 ( 21g Eb5s mb6s Mb7s xxxx ) no matter what Silver plays. Dd5 and Rg5 can't be saved anyway. 20g Eb5s mb6s Ha6e ra7s is another attacking move I like here.


What about:
20g: rb7n Mc7w Cd2n De2n
20s: Dd5n ed4n Dd6e ed5n
21g: Eb5s mb6s Mb7s Rh1n
21s: dc6n ed6w ec6e Mb6e (Capturing our camel)

The trouble with occupying b6 with the camel is that it means we are unlikely to get a replacement piece to c7, forcing us to commit the elephant to defence of c6, making it difficult to make threats in the future.
Title: Re: 2015 Move 20g
Post by Heyckie on Apr 17th, 2016, 1:10pm

After 20g rb7n Mc7w De2n Cd2n
20s Dd5n ed4n Dd6e ed5n would be a mistake because of
21g Cd3n Rc4w hc5s Eb5e.
E is tied to c6 but can threaten captures to c3, first h and later m.
Title: Re: 2015 Move 20g
Post by supersamu on Apr 17th, 2016, 2:55pm

on 04/17/16 at 11:25:37, Heyckie wrote:
Please, could you give an actual 20s refuting 20g rb7n Mc7w De2n Cd2n ? It seems to me we get our M to b6 ( 21g Eb5s mb6s Mb7s xxxx ) no matter what Silver plays. Dd5 and Rg5 can't be saved anyway. 20g Eb5s mb6s Ha6e ra7s is another attacking move I like here.


I think a good refutation to
20g rb7n Mc7w De2n Cd2n
is
20s Dd5n ed4n de5s de4w.
Silver threatens the capture in f6 and even if the gold camel occupies b6 with the Elephant pull, there is no capture threat since the c5 square is blockaded.

And the trouble with
20g Eb5s mb6s Ha6e ra7s
is
20s rc8w rb7w Hb6n mb5n
, after which the silver camel is out of reach of our elephant, and both our camel and horse are only used to share control of a trap.

(Responding to previous post now: )

21s de5s Cd4n de4w dd4s seems like a good continuation for silver there, imo.
Title: Re: 2015 Move 20g
Post by Hippo on Apr 17th, 2016, 4:01pm
OK, seems all proposed moves were refuted ...
Title: Re: 2015 Move 20g
Post by Heyckie on Apr 17th, 2016, 6:28pm
After 20g rb7n Mc7w Cd2n De2n
20s Dd5n ed4n de5s de4w
there's still
21g Eb5s mb6s Eb4w/s mb5s and maybe get a not-so-good camel hostage for the already pretty much lost dog and rabbit; doesn't amount to that much but neither does anything else.
Title: Re: 2015 Move 20g
Post by Lion on Apr 17th, 2016, 11:15pm

on 04/17/16 at 04:41:20, Hippo wrote:
It was my 2nd proposal ... see my 1st post
(and aaaa's one post earlier).


I should have been clearer. I meant that the b2 rabbit go to a4, not the c4 rabbit. Specifically, what about Rb2->a4 and the either Hg3->f3 or De2->e3 (probably the latter)? The idea would be to sacrifice the dog, but get the enemy camel + elephant occupied around c3, and use this time to advance the g3 horse toward c6 (come what may near g3).
Title: Re: 2015 Move 20g
Post by Hippo on Apr 19th, 2016, 12:26pm

on 04/17/16 at 23:15:08, Lion wrote:
I should have been clearer. I meant that the b2 rabbit go to a4, not the c4 rabbit. Specifically, what about Rb2->a4 and the either Hg3->f3 or De2->e3 (probably the latter)? The idea would be to sacrifice the dog, but get the enemy camel + elephant occupied around c3, and use this time to advance the g3 horse toward c6 (come what may near g3).


One variant (not deeply analysed):
20g Rb2w Ra2n Ra3n De2n 20s Rc4w hc5s Dd5w ed4n with threat 21s ed5n de5w cd7e ed6n
Title: Re: 2015 Move 20g
Post by Hufflepup on Apr 19th, 2016, 3:35pm

Quote:
And the trouble with  
20g Eb5s mb6s Ha6e ra7s  
is  
20s rc8w rb7w Hb6n mb5n
, after which the silver camel is out of reach of our elephant, and both our camel and horse are only used to share control of a trap.


I don't think this is a problem. Our position is slightly better now that the horse is freed, and on 21g we can move our elephant back to threaten the camel.

21g:Eb4n De2n Cd2n Dd3w
Title: Re: 2015 Move 20g
Post by Hufflepup on Apr 19th, 2016, 3:56pm

Quote:
I should have been clearer. I meant that the b2 rabbit go to a4, not the c4 rabbit. Specifically, what about Rb2->a4 and the either Hg3->f3 or De2->e3 (probably the latter)? The idea would be to sacrifice the dog, but get the enemy camel + elephant occupied around c3, and use this time to advance the g3 horse toward c6 (come what may near g3).


I'm concerned that advancing another rabbit will just make it easier for silve to blockade our elephant. Our existing advanced rabbits are causing enough trouble as it is. If we switched wings with the g3 horse silver will have the strongest free piece in the east, and with the h5 rabbit poised to advance it looks like silver could attack faster than we coould.


Quote:
One variant (not deeply analysed):
20g Rb2w Ra2n Ra3n De2n 20s Rc4w hc5s Dd5w ed4n with threat 21s ed5n de5w cd7e ed6n


20s: Rc4w ed4w X X

Would lead to a nasty elephant blockade.
Title: Re: 2015 Move 20g
Post by Lion on Apr 20th, 2016, 4:35am
Yeah, I missed 20s: Rc4w ed4w X X That does look pretty bad. The position looks pretty resignable, then--at least against "sharpvector."
Title: Re: 2015 Move 20g
Post by deep_blue on Apr 20th, 2016, 10:14am
What was so terribly wrong with the move I suggested? 20g Eb5s hc5w Rc4n Eb4e may not be a great move but it's not like we should resign there.
Title: Re: 2015 Move 20g
Post by deep_blue on Apr 21st, 2016, 11:39am
Only 4 people participated in the poll so it's no big surprise it was a tie... :/
Since we don't have enough time for a re-poll I broke the tie myself and decided on 20g Eb5s mb6s Ha6e ra7s. (I liked the other move a lot more but looking at the result matrix http://civs.cs.cornell.edu/cgi-bin/results.pl?id=E_4ecdb1c95111608a at least to me looks like this one was preferred)


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