Idea carried out from the problemists private forum.
The rules of this thread are as follows:
1) Look at the most recent post, it will be a chess puzzle.
2) Solve this chess puzzle.
3) Change it slightly by adding/removing/moving pieces (as few changes as possible. Preferably only 2 changes. 3 is really pushing it but is allowed if it doesn't change the position too much.)
4) Change the stipulation (optional)
5) Post a reply with the answer to the previous puzzle, and your new, altered puzzle.
6) Try and get your new puzzle to have a different key move to the last one.
7) No fairy pieces, but odd stipulations are allowed.
8) For the love of all that is good, don't cook it.
9) Don't point out that other people have cooked, or point out that other people have broken the rules, this just clutters the thread.
OK, first position:
White to play and #2
Originally posted by doodinthemoodThis problem has a dual.
Idea carried out from the problemists private forum.
The rules of this thread are as follows:
1) Look at the most recent post, it will be a chess puzzle.
2) Solve this chess puzzle.
3) Change it slightly by adding/removing/moving pieces (as few changes as possible. Preferably only 2 changes. 3 is really pushing it but is allowed if it doesn't cha the thread.
OK, first position:
[fen]8/P1P5/8/k7/2K5/8/8/8[/fen]
White to play and #2
1.c8(N)! Ka4 2.a8(Q)# or 2.a8(R)#
Originally posted by David113Hmm.. I always try to work them out of my problems. It's just not as pleasing as when you can only promote to one piece. That's just my opinion but you're more experienced to me so I defer.
Promotion to Q/B or to Q/R in the last move of a directmover is usually not considered a dual that spoils the problem.
I do so like my rule #9. So much I'm going to read it again to myself. Blimey that was a well-written, concise rule.
Anyway, someone solved the puzzle, but didn't post an altered one, so I'll field that bit this time...
2) Swap the king and a7 pawn, then add a bishop to c6
#2
Originally posted by doodinthemoodWell, it isn't very clearly written if it doesn't include what happens in the even of a dual. 😉
I do so like my rule #9. So much I'm going to read it again to myself. Blimey that was a well-written, concise rule.
Anyway, someone solved the puzzle, but didn't post an altered one, so I'll field that bit this time...
2) Swap the king and a7 pawn, then add a bishop to c6
[fen]8/k1P5/2B5/P7/2K5/8/8/8[/fen]
#2
But it doesn't really matter since, according to David, that isn't a disastrous dual.
Originally posted by doodinthemood1.c8(R) Ka6 2.Ra8#
I do so like my rule #9. So much I'm going to read it again to myself. Blimey that was a well-written, concise rule.
Anyway, someone solved the puzzle, but didn't post an altered one, so I'll field that bit this time...
2) Swap the king and a7 pawn, then add a bishop to c6
[fen]8/k1P5/2B5/P7/2K5/8/8/8[/fen]
#2
Originally posted by doodinthemood
I do so like my rule #9. So much I'm going to read it again to myself. Blimey that was a well-written, concise rule.
Anyway, someone solved the puzzle, but didn't post an altered one, so I'll field that bit this time...
2) Swap the king and a7 pawn, then add a bishop to c6
[fen]8/k1P5/2B5/P7/1K6/8/8/8[/fen]
#2
#3
1.nf5! [2.Qg7#] 1…Ke5 2.Qg4 [3.Qd4#] Kf6 3.Qg7#
Unfortunately, the key takes an unprovided flight: e7.
Note: the exception to rule 9 -- not a seperate post, thus no clutter.
It is our duty to point out flaws, to raise the level of contributions.
After the key move, shift wQg2->g3, then slightly alter the aim:
White to move and force a model-mate in 3 moves.
If you don't know what model-mate is, see:
http://en.wikipedia.org/wiki/Model_mate
In this example, this essentially means that all remaining* white officers (save wKing) must participate in the checkmate, and no square in the black King's field may be attacked by more than one white unit (counting flights taken by wKing too!).
* obviously, white units shed prior to the final coup need not participate.
Note: 1.Qg7?? fails, because bK has no legal moves, and the final position is not a model mate (e7 is attacked twice: by wQ + wN).
1.Qg4! (zz)
1…Ng7 2.Qxg7#
1…Nf4 2.Qg7#
1…Ng3 2.Qg7#
1…Ke5 2.Qd4#
Nice!
Toggle the color of all pieces, then alter the stip.
Circe Exchange
series.#6
White plays a series of 6 moves (premature checks end white's series), ending in checkmate of black King.
Circe Exchange: Captured units (except Kings) are immediately reborn onto the square just vacated by the capturing unit.
e.g., if black played ...Nxh6, +wNf5. If bK were on d6, ...Nxh6 would be illegal.
No rule about solving my own problem, so...
1.Nxf5 [+bNh6]
2.Nd6
3.f8=Q
4.Qg8
5.Qxg3 [+bQg8]
6.Qa3# (6...Kxa3 [+wQb4]+?? illegal by self-check).
So, same diagram, just remove fairy condition and change the aim:
helpmate in 3 moves.
Black moves first, then players take turns, both conspiring to allow a checkmate of the black king after black's 3rd move.