Originally posted by THUDandBLUNDERAre you sure about the position?
[fen]8/Bk3p1p/1P3p2/KP2n2p/1P1p4/1Pp2p2/b1P57B[/fen]
After 1.Ka4 Bb1 2.Ka3 Bxc2 Black promotes the d pawn anad mates.
after 1.Bb8 Kxb8 2.Ka6 d3 Black promote the d- or the c - pawn and wins;
after 1.Bxf3 Nxf3 or, 1.Bg2 fxg the same would happen.
In that case I guess the first move is 1.Bb1.
Though it is obvious White's king should descend to a1, then the bishop should return to a2 and the king procceds through the first rank I am missing the strategical concept behind it. May it be that White must force Black to move all of their pawns and for that matter they need to control the possible breach point at c2 with the king allowing for Bb1-Ba2 type of "empty" moves?
Originally posted by ilywrinNotice that in the starting position black is in zugzwang. A king move results in mate (1. ... Ka8 2. Ka6 and 3. b7#, 1. ... Kc8 also results in checkmate however it is longer). The knight is also stuck defending the f3 pawn.
In that case I guess the first move is 1.Bb1.
Though it is obvious White's king should descend to a1, then the bishop should return to a2 and the king procceds through the first rank I am missing the strategical concept behind it. May it ...[text shortened]... at c2 with the king allowing for Bb1-Ba2 type of "empty" moves?
With 1. Bb1 white forces black to move a pawn as all other moves lose. Now the white king moves down the board. 2. Ka4 (All other moves lose). The white king can no longer reach a6 so black can shuffle back and forth between a8 and b7. Now it seems clear that white must reach a5 (threatening a6) when black's king is on b7 forcing a pawn move. That means white must lose a move, through triangulation. The closest place is is f1-f2-e1. So of the white king goes:
1.Bb1 h6 2. Ka4 Ka8 3.Ka3 Kb7 4.Ka2 Ka8 5.Ka1 Kb7 6.Ba2 Ka8 7.Kb1 Kb7 8.Kc1 Ka8 9.Kd1 Kb7 10.Ke1 Ka8 11.Bb1 (if 11. Kf1 then d3 -+ ) Kb7 12.Kf1 Ka8 13.Kf2 Kb7 14.Ke1 Ka8 15.Kd1 Kb7 16.Kc1 Ka8 17.Ba2 Kb7 18.Kb1 Ka8 19.Ka1 Kb7 20.Bb1 Ka8 21.Ka2 Kb7 22.Ka3 Ka8 23.Ka4 Kb7 24.Ka5
Now black cannot play Ka8 as shown before.
24. ... h4
This repeats and every 23rd move hereafter black must move a pawn eg. 47, 70, 93, 116, 139, 162, 185, 208 and 231.
After move 231 white continues as before with the long walk to triangulation. However this time when he returns black won't have a pawn to move.
Postion after 254. Ka5
The longest way to mate here is for black to play 254. Kc8 I believe. However working out the best play from here is too long a task for me to undertake (I'm lazy).
Originally posted by bobbob1056thSeems legal to me.
In which case the position is illegal.
White makes 7 P captures - Black is missing 7 units.
Black makes 6 P captures - White is missing 7 units.
White played fxe, then promoted on e8 to obtain the third Bishop.
Black promoted his a-pawn after White played axb. In this manner, the missing a-pawn becomes useful for sacrifice.
originally posted by bigdogproblemOr the a-pawn promoted to knight and moved to e5... Yes it is legal.
Seems legal to me.
White makes 7 P captures - Black is missing 7 units.
Black makes 6 P captures - White is missing 7 units.
White played fxe, then promoted on e8 to obtain the third Bishop.
Black promoted his a-pawn after White played axb. In this manner, the missing a-pawn becomes useful for sacrifice.
OMG, the day I actually attempt to understand a puzzle like this, I will know my chess addiction has reached a whole new level.
Which is not to be nasty to those of you who DO understand it, I'm just saying that anything that expects me to see more than a few moves ahead is so beyond the realms of understanding, it might as well be written in Swahili.