White has 9 units and Black has 15. White's only capture was exQd~ (doubled pawns). Black needs to uncapture all 7 missing White units with pawns, to restore the pawn structure and allow wP's to return home.
wPa and Ph must sacrifice themselves to Black pawns, and the only way to do it is to promote both pawns (no uncaptures possible on the a- or h- files). This means, before Black can retract axb and hxg, White pawns must un-promote and retract back far enough where they are not 'trapped' behind a black pawn once it un-captures.
Particularly difficult is the a-pawn promotion. The NW corner needs to be unlocked to solve the problem (after all, giving one or both Kings moves is the usual way to solve retros), but there is very limited space there. Nevertheless, with careful use of pawn tempos, there is just enough time and space to pull it off.
Why unpromote an N and then uncapture N?! The subtle motivation is to save Black a pawn tempo that he'll need later. If the original N charges into the NW corner, Black will have to spend both pawn tempos to let him in.
Originally posted by BigDoggProblem White has 9 units and Black has 15. White's only capture was exQd~ (doubled pawns). Black needs to uncapture all 7 missing White units with pawns, to restore the pawn structure and allow wP's to return home.
wPa and Ph must sacrifice themselves to Black pawns, and the only way to do it is to promote both pawns (no uncaptures possible on the a- or h ...[text shortened]... k here, if the h-pawn was already on h7.
[b]33...h7 34.a6 Na7 35.a5 b5a6(+Rb5) etc.[/b]
How have you managed to lose games when you can solve puzzles like these?
Originally posted by cmsMaster How have you managed to lose games when you can solve puzzles like these?
Solving retros and other esoteric chess problems is quite a different world from Chess, the game. Problems like retros and helpmates involve cooperative play between White and Black, rather than competitive play.
In a problem, you know that there is something specific and logical to find within the position. In a chess game, there are no guarantees and no stipulations to tell you what result to play for.
Originally posted by BigDoggProblem Solving retros and other esoteric chess problems is quite a different world from Chess, the game. Problems like retros and helpmates involve cooperative play between White and Black, rather than competitive play.
In a problem, you know that there is something specific and logical to find within the position. In a chess game, there are no guarantees and no stipulations to tell you what result to play for.
I'm just saying, if you can solve all of these problems, then you should be rated at least 2000.
A retro by Ceriani
28 Aug '06 11:31
Back to Top