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        Team Games >> 2009 One vs TheMob >> 2015 Move 11g
        
(Message started by: half_integer on Dec 6th, 2015, 9:00pm)
Title: 2015 Move 11g
Post by half_integer on Dec 6th, 2015, 9:00pm
Sharp-lv has moved.  It is a slightly different move than I was anticipating:
    10s mg4n de6e mg5w Rh5w
moving the dog to f6 keeps the camel unfrozen and allows a four-step capture of our rabbit.  I think this capture is silver's goal; the h-file threat is too easily blocked.

Pull-and-replace on g3 doesn't appear profitable:  11g :Hg4 Hg3 is answered with 11s Me5:R Rg5 Hh4 and we're left with the loss of a rabbit and no threats.

Flipping the b6 horse seems appealing:  11g ::Hb4 11s Dd3 Rb6 12g ::Hb2 and silver's left side looks weak while we have threats greater than the rabbit he's holding at risk.

Thoughts?
Title: Re: 2015 Move 11g
Post by aaaa on Dec 6th, 2015, 10:05pm
What if Silver just takes the rabbit after the horse flip? If Gold then captures the horse, the silver camel can immediately threaten the gold horse with capture and the tactics from there on look very tough.
Title: Re: 2015 Move 11g
Post by SilverMitt on Dec 7th, 2015, 1:56pm
After 11g ::Hb4, taking the rabbit is almost certainly suboptimal, and I don't think it can serve as a refutation, as 11s Me5 De6 xg5 12g Mc4xH 12s Mb6 13g Mc5 ab5 Eg4 Hf4 seems to be in our favor.  I'd be more concerned with any line including at least one step of the h6 rabbit.

After 11g :Hg4 Hg3 11s Me5:R g5 Hh4, I'm not concerned with the rabbit so much as the silver elephant being able to move west next turn, though I suppose we may not be disagreeing on much here.  I don't have a great feel for such positions, but I guess it would be our turn to try to make something happen in the west without giving up a good hostage, while the east would be relatively secure for the near future.
Title: Re: 2015 Move 11g
Post by Hufflepup on Dec 8th, 2015, 4:02pm

Quote:
moving the dog to f6 keeps the camel unfrozen and allows a four-step capture of our rabbit.  I think this capture is silver's goal; the h-file threat is too easily blocked.


Whilst it can be blocked easily in the short term a silver rabbit at h2 could become a major strategic problem in the longer term. If we allow this move next turn I wouldn't be surprised if silver played it with the intention of capturing the rabbit on 12s.


Quote:
Pull-and-replace on g3 doesn't appear profitable:  11g :Hg4 Hg3 is answered with 11s Me5:R Rg5 Hh4 and we're left with the loss of a rabbit and no threats.


What about the horse flip on 12g: Mb5e hb6s hb5s Mc5w?
If silver takes the rabbit we can now take the horse, if the silver camel came east to take our horse hostage 12s: me5w md5w mc5n mc6w our elephant is now free to switch wings with 13g: Ef4w Ee4w Ed4w Ec4n . On 13s silver probably captures the rabbit and switches wings with the elephant to avoid losing the horse. This allows us to take the horse hostage with the camel on 14g.

Our advanced rabbit in the west means we should be in a better position to exploit our hostage than Sharp is. We do go a rabbit down, but given the position this may not be avoidable.


Quote:
After 11g ::Hb4, taking the rabbit is almost certainly suboptimal, and I don't think it can serve as a refutation, as 11s Me5 De6 xg5 12g Mc4xH 12s Mb6 13g Mc5 ab5 Eg4 Hf4 seems to be in our favor.  I'd be more concerned with any line including at least one step of the h6 rabbit.


What about 13s: ee3n Hf4n ee4e de6s making a counter threat to our horse. Our camel is in a very exposed position at c5.  If silver was able to switch wings with the elephant we would be in a lot of trouble in the west.
Title: Re: 2015 Move 11g
Post by SilverMitt on Dec 9th, 2015, 3:35pm
It does seem like pull-and-replace on g3 and the horse flip are our main ideas, and a rabbit loss, with potential compensation, is likely.  What's left is to work out the tactical possibilities to see which to do first.
Title: Re: 2015 Move 11g
Post by aaaa on Dec 9th, 2015, 7:10pm

on 12/08/15 at 16:02:49, Hufflepup wrote:
What about 13s: ee3n Hf4n ee4e de6s making a counter threat to our horse. Our camel is in a very exposed position at c5.  If silver was able to switch wings with the elephant we would be in a lot of trouble in the west

Indeed and 13g Mc4n Ra5e Ef4e Rf1w could be answered by a horse flip.
Title: Re: 2015 Move 11g
Post by SilverMitt on Dec 10th, 2015, 12:19pm
I find 11g g4:H Hg3 much preferable to 11g M::Hb4 now.  Are there any other worthy candidate moves?

On a side note, I don't actually think that after 11g g4:H Hg3 11s Me5:R g5 Hh4 12g M::Hb4 12s Mb6, 13g Ec5 is particularly good, because I don't see a way to get a horse hostage after 13s Ec4 x.
Title: Re: 2015 Move 11g
Post by aaaa on Dec 10th, 2015, 2:22pm
To throw in another idea: 11g Mb5e hb6s Ha6e Dd2n, sacrificing the rabbit to start a counterattack in the northwest.
Title: Re: 2015 Move 11g
Post by clyring on Dec 10th, 2015, 4:58pm
If we anticipate the silver camel coming west, it would be very nice to get our eastern horse into a more aggressive posture. (...is an opinion without any analysis supporting it.)
Title: Re: 2015 Move 11g
Post by half_integer on Dec 10th, 2015, 9:05pm
aaaa, could you provide more detail on your idea to attack c6?  I don't see just the two pieces being able to make a threat of capture quickly.

As far as enumerating possible moves, there are actually seven moves which move the Hb6 two steps closer to the c3 trap.  If we are considering the flip as a likely move, we should ensure none of them are slightly better.

Along with the horse pull-and-replace, there is another move we could consider: something along the lines of Rg2e Cf2e Hf3s X .  It is a quieter move and not necessarily the best, but it should be examined.

Honestly, I'm a little worried if only the moves I've suggested are being considered :-) .  I expect the rest of you to come up with moves that I have missed.

I have some comments on the anticipated lines that have been posted, but that will have to wait until tomorrow.
Title: Re: 2015 Move 11g
Post by aaaa on Dec 11th, 2015, 3:08pm

on 12/10/15 at 21:05:05, half_integer wrote:
aaaa, could you provide more detail on your idea to attack c6?  I don't see just the two pieces being able to make a threat of capture quickly.

The idea was to activate the horse on a6, as a recurring theme in this discussion has been that it's not doing much there except being bait for the enemy camel.


Quote:
As far as enumerating possible moves, there are actually seven moves which move the Hb6 two steps closer to the c3 trap.  If we are considering the flip as a likely move, we should ensure none of them are slightly better.

If the goal is to stop Silver from winning a net rabbit, the tactics don't seem to work out any better.


Quote:
Along with the horse pull-and-replace, there is another move we could consider: something along the lines of Rg2e Cf2e Hf3s X .  It is a quieter move and not necessarily the best, but it should be examined.

It's completely baffling to me why one would prefer having one's horse on f2 instead of g3.


Quote:
Honestly, I'm a little worried if only the moves I've suggested are being considered :-) .  I expect the rest of you to come up with moves that I have missed.

Finding only one move that stands out could be a bit worrisome, but 11g Ef4e Eg4w hg3n Hf3e appears to be more than just the least bad option for several reasons, so this might be one candidate for a voice vote.
Title: Re: 2015 Move 11g
Post by half_integer on Dec 12th, 2015, 11:52am
Perhaps I managed to miss something, but despite a few people stating they now prefer the horse pull-and-replace I didn't see an explanation of why, nor a clear refutation of the horse flip.

As SilverMitt said in post #2, after the horse replacement and my conjectured silver response, "I'm not concerned with the rabbit so much as the silver elephant being able to move west next turn" - I agree, and doesn't this negate the idea of doing the horse pull now and the western horse flip next turn since the elephant can defend c3?

Regarding aaaa's question about why make the quiet move with H->f2 instead of replace on g3, the easiest answer is because it doesn't take all four steps, and blocks the h file.  I agree that horse on g3 is nice, but is it worth using the entire move to achieve it?

The horse flip appear to lead to either we get a hostage for losing the rabbit, or we have facing horse hostages (and I agree we're in better position due to the a file rabbit).  Actually, the response that most concerns me right now is Ec4 Hh3 as we can't immediately get the hostage nor capture in f3 due to our horse.

I'm willing to be convinced but I need to see the lines.  It would be great if we had an actual tree for this move so we're all making the same assumptions about likely lines.
Title: Re: 2015 Move 11g
Post by Hufflepup on Dec 12th, 2015, 2:07pm

Quote:
Regarding aaaa's question about why make the quiet move with H->f2 instead of replace on g3, the easiest answer is because it doesn't take all four steps, and blocks the h file.  I agree that horse on g3 is nice, but is it worth using the entire move to achieve it?


H->g3 also blocks the h file to a rabbit advance next turn and we could block it with a rabbit if desired next turn. It also improves our control of the trap allowing us to relocate the elephant next turn if required. I think this is worth more than anything we could gain by making a 4th step elsewhere. Addittionally H->g3 forces silver to spend time defending against our threat to frame the silver horse.


Quote:
The horse flip appear to lead to either we get a hostage for losing the rabbit, or we have facing horse hostages (and I agree we're in better position due to the a file rabbit).  Actually, the response that most concerns me right now is Ec4 Hh3 as we can't immediately get the hostage nor capture in f3 due to our horse.


The situation after Ec4 Hh3 looks OK, but I am more worried about the defence 11s: rh6s rh5s rh4s rh3s which is prevented by pulling and replacing the horse.
Title: Re: 2015 Move 11g
Post by half_integer on Dec 12th, 2015, 2:34pm
Note that any silver advance of the h-file rabbit allows us to make counterthreats after defending, so we would both be able to constrain each others' moves.

For example, 11s Rh2 12g Rh1 Rg1 Eg4 Rh5 (note the horse can't be taken without loss in one)
Title: Re: 2015 Move 11g
Post by half_integer on Dec 12th, 2015, 7:36pm
Here is a tree.  Feel free to copy and edit in more lines or commentary.

Move 11g – using SilverMitt notation for practice
Steps in parens are samples for a family of moves

1  :Hg4 Hg3 (slight negative)
   1.1  Me5:R Rg5 Hh4 (slight negative - silver elephant is now free to leave f3)
   1.2  Me5:R De6:Rx (slight negative – weak horse frame for rabbit loss)

2  ::Hb4 (??? to slight advantage)
   2.1  Dd3 (Rb6)
         2.1.1  M::Hb2 (good for gold)
   2.2  Dd3 Rh5 (h file threat must be responded to)
         2.2.1  :Hg4 Hg3 (OK for gold)
   2.3  Ec4 Hh3 (???)
         2.3.1  (What is the best response?)
   2.4  Me5:R De6:Rx
         2.4.1  Mc4::Hc3x (end with camel on c4 to move to c5 after...)
            2.4.1.1  Mb6 (slight advantage for gold?)

3  Ma4::H (similar to 2)

4  Mb3::H (allows horse escape to west)

5  Mc4::Hb4 (allows horse escape to west)

6  ::Hc5 (silver can retreat horse)

7  Mc4::Hc5 (silver can retreat horse)

8  Md5::H (silver can retreat horse)

9  Mc6x::H / Mx::Hc5 (clearly bad, suicide of caMel)

10  Mc5:H Hb6 (Ra3)
   10.1  Me5:R De6:Rx (slight negative – no compensation for rabbit)

11  Rh2 Cg2 Hf2 (Ra3)
   11.1  Me5:R De6:Rx (slight negative – rabbit loss but h file blocked)

12  Rh1 Rg1 Cf1 Hf2
   12.1  Me5:R De6:Rx (slight negative – rabbit loss but h file blocked)
Title: Re: 2015 Move 11g
Post by SilverMitt on Dec 12th, 2015, 8:51pm
For 1.2, I actually think the frame is pretty strong, as I don't believe silver can try to break it with the attack in the west.  But with the silver camel going west, our a6 horse remains vulnerable; we would probably want to avoid a horse trade.
Title: Re: 2015 Move 11g
Post by browni3141 on Dec 13th, 2015, 4:46am
I have trouble deciding between the two moves.

I agree with SilverMitt that 1.2 isn't concerning. Nor do I think 1.1 is.

I like gold after

11g Ef4e Eg4w hg3n Hf3e
11s mf5w Rg5w rg6s hg4e
12g Mb5e hb6s Ef4w Ee4w

I struggle to come up with a clearly best reply for silver against either 11g.


11g Mb5e hb6s hb5s Mc5w
11s mf5w Rg5w rg6s rh6s is the most testing that I can see.
Title: Re: 2015 Move 11g
Post by half_integer on Dec 13th, 2015, 3:45pm
Deep says we're about to move, so I'll just comment that I agree with both the last two posts.  The frame in 1.2 does appear stronger on second look; it is true that although the camel can break it, we can do damage in the west before he does so.  If he doesn't abandon the frame the best silver can do is both elephant and camel deadlock.

Given that analysis, I actually think 1.1 will be the response move.  Browni's response is a good addition to the move tree.  It seems to me that if that line gets played, there is a good chance that silver will return to attacking the f3 trap on 12s.

This is an interesting point in the game.  It seems like we're near the point where either we lose a rabbit for little compensation, making the game more difficult going forward; or we show that sharp-lv failed to look far enough ahead strategically and we gain more compensation than the rabbit that he threatens.
Title: Re: 2015 Move 11g
Post by half_integer on Dec 13th, 2015, 9:06pm
I'll just use this thread to continue the analysis post-move 11g.  Here are some silver responses and potential replies.

1  :Hg4 Hg3
- 1.1  Me5:R Rg5 Hh4 (silver elephant is now free to leave f3)
- - 1.1.1 Mc5:H Ed4 (browni's suggestion)
- - - 1.1.1.1 Mf3 (Rh5) (just a sample to restart the f3 fight)
- - - 1.1.1.2 Me6 Ed5 (probably not a very good move)
- - 1.1.2 ::Hb4
- 1.2  Me5:R De6:Rx (horse frame for rabbit loss)
- - 1.2.1 ::Hf3
- - - 1.2.1.1 Mg5 (De5 or Cf6) Rh5 (prepare to break the frame)
- - - - 1.2.1.1.1 Mc4::H
- - - - - 1.2.1.1.1.1 Xb5 Ha4
- - - 1.2.1.2 Mc5 X X (deadlock c6 or M+D attack c3)
- 1.3 Me4:R Dd5 (diamond defense to prevent frame)
- - 1.3.1 ::Hb4
- - - 1.3.2 Md3/c4 De4
- - - - 1.3.2.1 Ed4:De5 Rcd1 (OK maybe this refutes the line for silver)
- 1.4 Me4 Df5 (Cf6) (another diamond defense variant)
- 1.5 Me4:R Rg5 (diamond defense with some goal attack)
- - 1.5.1 ::Hb4
- - - 1.5.1.1 Rh3 Md4 (at least one step needed for goal defense)
- - 1.5.2 Re5 Mc5:H Hb6 (maybe Rh1 is better 4th step)
- - - 1.5.2.1 Rh3 Df5 (goal threat with diamond re-established)
- - - 1.5.2.2 De5:Rf5 Rh5 (maintain control of rabbit, re-establish diamond, and maneuver into goal attack)

Of course these are more speculative the deeper they go and I wrote them out quickly.  I hope they are easier to read this time; I track the side to move by noting whether the indent is an even or odd amount but the move numbers could be added.

Any other good silver 11s moves?
Title: Re: 2015 Move 11g
Post by SilverMitt on Dec 14th, 2015, 3:08pm
An interesting 11s might be something that includes Ee4.D.
Title: Re: 2015 Move 11g
Post by half_integer on Dec 14th, 2015, 9:10pm
Ah, the Ec4:D is a nice addition to the possible moves which prevent the frame.  Perhaps Ec4:D Me5 Df5 with the idea that the camel can deadlock in the west as long as the elephants are kept deadlocked.  However, I don't see it holding long term (see below).

I see that 12g Mc5:H Hb6 Rcd1 can refute putting the silver camel on e4, as 13g E::Md3 then becomes indefensible for silver.  A goal threat on the h-file could slow it down but gold will get enough steps at some point.  Retreating the horse seems like the only option, since putting the silver elephant on e4 with a pull to e3 won't hold long term; the e3 piece can be retreated and become a 3-for-1.  Does anyone see other possibilities for holding a diamond defense?

If 1.3, 1.4, and 1.5 are refuted for silver, that leaves 1.1 as the most likely move IMO.


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