A.Buchanan: WinChloe rokagogo only finds the intended solutions, no real P-M duals and no fake rokagogo duals:
1.Cé7 F×h4 2.Rg8(Tf8) F×f6 3.Tf7 Th8‡
1.é1=T Ff1 2.Ré6(Té7) F×d3 3.Rd5 Fç4‡
1.Fa7 b6 2.Rç8(Td8) b×a7 3.Td7 a8=D‡ (2021-01-06)
Henrik Juel: Solutions 1 and 2 are also C+ by Popeye 4.61
The joke castling in solution 3 brings sKe8 to e6 and promoted sTe1 to e7 (2020-04-03, hidden) more ...
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Henrik Juel: Here the extra joke is that the (dummy) pawn can move (2020-04-14)
James Malcom: The newly born black pawn is not a dummy pawn, in my opinion. Unlike the dummy, it still has the right to move foward in principal. Since it is new and has never moved, it sill has the right to make a double-step if allowed, as in Horde Chess (https://lichess.org/variant/horde). (2020-04-14)
Henrik Juel: I see your point, James (2020-04-15)
James Malcom: Seems that Gerd might have missed including pawns promoting to opposite color pawns the new update. I'll email him tomorrow morning. With accordance to the rules, they have 4 first moves as a 7th rank pawn does. (2020-05-03)
Gerd Wilts: Promotions to pawns are now also supported. (2020-05-03)
James Malcom: Many thanks Gerd! (2020-05-03)
A.Buchanan: I had missed these 6 miniatures: they are terrific! Can I ask to replace Sg8 in this one with L so that it's not giving check in the starting position. I guess it's kind of crass though economical to replace with pawn! (2020-10-13)
A.Buchanan: Dummy pawns can in principle move imho: it's just that they're usually blocked by the edge of the board. If one was teleported somewhere else on the board by some mechanism, then they would just start moving. So completely different kind of animal from a dummy, which genuinely cannot move :D (2020-10-13)
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Henrik Juel: 1:00 AM, I guess
With 24 hour notation, between 24 and 01 (2022-02-26)
Henrik Juel: Nice double white promotion to sT (2022-02-26)
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A.Buchanan: Hi James, tiny point. Does 1. ... La7 allow both 2. GKxf6xd4# and 2. Lxe5# ? Can this be fixed by shifting wBc7 to b8? (2023-07-01)
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James Malcom: As far as I know, this is the first presentation in a selfmate. Of course it can be argued that a Belen only constitutes White castling with mate, but as far as I see it as long as the BK's journey is done and the last move is White's castling, it is a Belen. haven't seen any opposition to this as I have seen. (2020-09-21)
James Malcom: I won't be surprised if this was cooked, however: it is untested and never has been. (2020-09-21, hidden)
SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-09-21, hidden) more ...
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-09-21, hidden) more ...
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James Malcom: This is the first Valladao-Belen with an underpromotion. However, it is damaged by the common "short" ep and a dualistic move order. (2020-09-21)
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Henrik Juel: C+ Popeye 4.61 (2020-09-21, hidden) more ...
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James Malcom: The first Valladao-Belen with a bishop promotion. (2020-09-22)
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James Malcom: Some months back, I managed to improve Hoffmann's P1380143. But has only been published recently alongside it, and ironically in the same month. The point here is that there is but a single solution. It turned out to be scarcely possible, requiring every White man but the queen. (2020-09-22)
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Henrik Juel: C+ Popeye 4.61, except for the mate dual after 2... Kxa3 (2020-09-22)
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SCHRECKE: C+, popeye 4.85 (2020-09-22, hidden) more ...
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Henrik Juel: Correct key, but damaged by multiple threats and duals, e.g.
1.Kd3 thr. 2.e8=DTLS,Ke4 (2020-09-27)
James Malcom: Typo fixed. And Henrik, the threats are not the point here. The point here is how the different play of the Black knight changes White's promotions. (2020-09-27)
A.Buchanan: It's a beautiful idea, still looking for its rendering though as the many duals and the obstreperous wL are quite distracting (2020-09-28)
James Malcom: There aren't any duals in full-length variations, though. The extra bishop is indeed annoying, but unfixable so far. (2020-09-28)
A.Buchanan: There are still some trivial duals in the mating move, but yes. This problem is trying to ignore threats: you can see that the computer solution. The solution is much more coherent with "nosh noth" switched on. So when are the cases, Henrik, when you switch those options on? It would be event better if one was able to switch threats on for the 4th move. This underscores that there should be a Popeye option for any white move "noth" is self-selecting, depending upon the number of variations. (2020-09-29)
Henrik Juel: Andrew, I use the Popeye option 'nosh' when the output without them is overwhelmingly large
The 'not' option is tricky, and usually expands the output; in some cases it shows apparent duals that are not real ones, when you apply the rule that dualistic play should be ignored, when it appears after black moves that do not prevent the threat
In the case of multiple threats things get messy, like in this problem, as I recall (2020-09-29)
Henrik Juel: tiny typo
1... Sf5 2.Lxf5, not Lxe5 (2020-09-27, hidden) more ...
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Henrik Juel: C+ Popeye 4.61 (except for a mate dual) (2020-09-27)
Stefan Felber: Forderung fehlt! (2020-09-27, hidden)
James Malcom: Whoops-added! (2020-10-13, hidden) more ...
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Henrik Juel: C+ Popeye 4.61 (but some of the short variations are dualistic) (2020-09-28, hidden) more ...
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A.Buchanan: I really like this one :-) (2020-10-01)
A.Buchanan: If you can start the bishops on f1 & g1, then could have #h4 with the end position being double platzwechsel. Easy to get the h#3.5 - shift Lf2 to g1 & change Be3 to White. I can't help the nagging feeling that I might have seen this double swap somewhere before, but I think it was Black doing the castling (2020-10-01)
Henrik Juel: C+ Popeye 4.61 (2020-09-30, hidden) more ...
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James Malcom: P1380523 is the only predecessor I know with the idea of castling with capture. (2020-10-02)
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SCHRECKE: ZU-Dual: 14.Th7 Ke8 15.Lc7 L:e7# (2020-10-17, hidden) more ...
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Henrik Juel: C+ Popeye 4.61 (2020-10-17, hidden) more ...
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Olaf Jenkner: wBg3, +wPh2 you get a model mate (2020-10-18)
A.Buchanan: Can one begin with wTa3b3 so there is a genuine try 1. Tb1? (2020-10-19)
James Malcom: It turns out that this record was actually done, doubled, by P1371538. So a 14 square route of the Black king appears to be the record, for now anyway. (2021-01-01)
Henrik Juel: Popeye 4.61 with 'opt non 0 1 thr 0' found no flaws (2020-10-17, hidden)
SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-10-18, hidden)
A.Buchanan: I think that’s pure mate not model? (2020-10-19, hidden)
A.Buchanan: Well Andrew: good question. With the current position, there is a cook rather than a dual, because wLd6 covers c5, and even if wLd6 was shifted as per Olaf's sensible idea, wD still covers the square, so we need a more drastic change, but it's surely worth doing (2020-10-19, hidden)
A.Buchanan: Rotate the board and sth like this maybe: r2N3k/q3PP2/Q2P4/K1P5/1PP5/8/5R2/NB3R2 (2020-10-19, hidden)
A.Buchanan: Simplest might be to take Olaf’s idea and then wTa2 to a3 and add sBe7. A rotation does it more economically but requires an officer for the square a7 which is rotated to the back rank (2020-10-20, hidden) more ...
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James Malcom: This composition is one of my personal favorites amongst mine. It was inspired be Krabbe's Journal #89, which touches on the so called theme of "remote knight promotion." The point of this is to show the aximum diaganol distance with kings and pawns only.

A Meredith rendering is still pending for any geniuses out there. (2020-10-24)
SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-10-24, hidden) more ...
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SCHRECKE: 1.a8=sS! (2020-10-24, hidden)
James Malcom: Correct! Solution added. (2020-10-24, hidden) more ...
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Henrik Juel: Slightly damaged by late duals after 2... Dd4 (2020-10-24)
James Malcom: But those are irrelevant, Henrik. (2020-10-24)
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James Malcom: I've added in the solution now. (2020-11-02)
Henrik Juel: Thanks, James
I cannot test the problem, but it seems OK (2020-11-02)
A.Buchanan: Thanks Henrik: it's C+ according to WinChloe (2020-11-03)
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-10-25, hidden) more ...
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-10-25, hidden)
Henrik Juel: The stipulation should be s#8, I think (2020-10-25, hidden)
James Malcom: Fixed. (2020-10-26, hidden) more ...
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A.Buchanan: Hi James, couple of nits about old Bosma:
(1) From the 1985 Laws: "Article 5. THE MOVES OF THE PIECES The King (a) Except when cast[l]ing, the king moves to any adjoining square that is not attacked by an opponent's piece." This is separate from Article 9. CHECK 9.1 "The king is In check when the square it occupies is attacked by one or two of the opponent's pieces; in this case the latter is or are said to be "checking the king.' 9.2 Check must be parried by the [move] immediately following." This point may have been an assumption in earlier compositions, as e.g. it prevents kings from being adjacent.
(2) And again from Article 5. "(f) Castling is prevented for the time being - (i) if the king's original square or the square which the king must cross over or that which it is to occupy is attacked by an opponent's piece," Does this prevent your 1.0-0?
What do you think? (2020-11-08)
James Malcom: Ah, why did I but never bother to look at the castling rules!

Well I see nothing against adjacent kings, and seeing about how the "loophole" was about was not explicitly stated couldn't be done, I see it as allowed, and thus what to watch out for in cooks.

The rule on castling says "piece," not pieces. So, quite simply, castling in, out (P1381498), and through (P1381499) check is allowed in my view. (2020-11-09)
James Malcom: Furthermore, if a king is "attacked," they are in check, plain and simple. So, since a triple check/ attack is not defined as a danger to the king, the king may go to any such square, including the acts of catling and adjacent kings.

Also, going by the law itself, and not the Bosma conditions, the king may be captured, but it does nothing and that side can never be checkmated, while Bosma Chess itself allows no king capture. But since the effect is the same, allowing for my jokes to be C+ by Winchloe if the program agrees. Maybe try out my castlings in it? (2020-11-09)
James Malcom: And indeed Andrew has tested my castling problems now-all are C+? (2020-11-14)
James Malcom: Typo-!, not ?. (2020-11-14)
A.Buchanan: Hi James, couple of nits about old Bosma:
(1) from the 1985 Laws: "Article 5. THE MOVES OF THE PIECES The King (a) Except when cast[l]ing, the king moves to any adjoining square that is not attacked by an opponent's piece." This is separate from Article 9. CHECK 9.1 "The king is In check when the square it occupies is attacked by one or two of the opponent's pieces; in this case the latter is or are said to be "checking the king.' 9.2 Check must be parried by the [move] immediately following."
(2) And again from Article 5. "(f) Castling is prevented for the time being - (i) if the king's original square or the square which the king must cross over or that which it is to occupy is attacked by an opponent's piece,"
Both of these points seem to prevent your #1. The first point also may have been an assumption in many early compositions, as it prevents kings from being adjacent. What do you think? (2020-11-08, hidden) more ...
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A.Buchanan: Nice way to combine an orthodox theme with Bosma castling (2020-11-13)
James Malcom: Thanks, Andrew. Castling with check is the easiest way to achieve it of course, not to mention the flight taking. I'll try out a version without check, here soon. (2020-11-13)
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James Malcom: The wSe1 prevents the orthodox cook of 1. ... Kxc2. (2020-11-14)
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A.Buchanan: Trivial verification, perhaps, but at least it confirms that WinChloe's understanding of the condition resembles James'. (2020-11-13)
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Henrik Juel: Popeye 4.61 with 'opt thr 1' found no flaws (2020-11-04, hidden)
James Malcom: I've managed a small extension, so do not computer test this yet. (2020-11-04, hidden)
Olaf Jenkner: Semi-finished problems should not be published. (2020-11-05, hidden)
James Malcom: I agree-this was a severe lapse in my judgement. (2020-11-05, hidden)
A.Buchanan: I think you’re being too hard on yourself, James. It’s hard to know when a problem is “finished”. Unless a position is just thrown together for a discussion, I tend to wait another sleep cycle to see if any more ideas pop up. But it’s not the end of the world if an electronically published problem gets improved a couple of days after the first post (2020-11-05, hidden)
James Malcom: I had had the previous position for a while now, but only yesterday did I see how to improve it. And the new position has now been entered. There are definite duals in the sidelines, but there is a forward, main, defense plan for Black. (2020-11-05, hidden) more ...
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Henrik Juel: C+ Popeye 4.61 (2020-11-12, hidden) more ...
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SCHRECKE: C+, popeye 4.85 (2020-11-12, hidden) more ...
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A.Buchanan: If one allows promotion to sB (and there seems no reason to disallow it since promotion to pawn, king and foreign units are allowed) then the problem is cooked. There is no universally agreed notion of how a pawn can move if it starts on the first rank. Does it get a double hop, and if so on which rank? But the problem is unsound in any case. (2022-02-10)
James Malcom: That is if, yes. But I don't think this problem ought to be left as is: a demonstration of the levels of absurdity and tomfoolery old rules used to allow. Promotion to a piece of another color and dummies were loopholes, yes, but promotion to a black pawn was never included, not even implicitly. All pawns are pieces, but not all pieces are pawns. (2022-02-10)
A.Buchanan: Can't White play 3. a8=DTLSB - basically any White unit? (2022-02-09, hidden)
James Malcom: No, as bNa8 is needed to guard c7. (2022-02-09, hidden) more ...
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SCHRECKE: C+, popeye 4.85 (2020-11-16, hidden) more ...
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Henrik Juel: No record, P1182074 is far better in terms of giving Black moves, 32
But this problem also a #2 (2020-11-22)
A.Buchanan: First record in a new task (2020-11-22)
James Malcom: Henrik, you misunderstood! The task is different from the 32! This is about Black release in the #2 form, not releae in the fairy form. (2020-11-22)
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-11-25)
James Malcom: Houston, we have a problem: I merely marked this as C+, and the entire position just disappeared?! (2020-12-30)
Gerd Wilts: Hi James, this was unfortunately a new bug introduced yesterday evening with a PDB update. It is now fixed. (2020-12-31)
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-12-04)
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-12-04)
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-12-04)
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Henrik Juel: C+ Popeye 4.61 (2020-12-04)
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HBae: 14 Züge wurden schon 1976 dargestellt, siehe P1178762 (2020-12-13)
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Henrik Juel: C+ Popeye 4.61 (2020-12-17)
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Henrik Juel: C+ Popeye 4.61 (2020-12-18, hidden) more ...
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2020-12-25)
Ladislav Packa: Construction can be more economical, the solution is the same:
Ka2, Pc2, f2, g2, h2 (5) - Kg6, Qc1, Rf4, Be8, Bg7, Pf6 (6)
C+ by Popeye v4.77 (2020-12-25)
James Malcom: Very beautiful economization Ladislav! (2020-12-26)
Olaf Jenkner: siehe auch die kürzere Fassung P1384242 (2020-12-26)
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SCHRECKE: Nebenlösung: 1.Lf7 ... 3.e7 4.Ld5 ... 8.a7 Lh2 9.Lc6 Lg1 10.L:g7+ Kg8 11.a8D+ Kf7 12.e8T Lh2 13.Le4 Lg1 14.Le5 Lh2 15.Dc6 Lg1 16.Dg6+ h:g6# (2021-01-01)
James Malcom: Are there any more cooks? (2021-01-02)
SCHRECKE: Diese NL hat viele Zugumstellungen, sonst fand ich nichts. (2021-01-03)
James Malcom: It's seemingly fitting that the cook produces an AUW. I presume that you used Gustav? (2021-01-03)
SCHRECKE: Yes (2021-01-03)
James Malcom: How does it fare with a white rook on h5 instead, so Bxg7+ doesn't work? (2021-01-03)
SCHRECKE: Maybe it's okay with wRh5. (2021-01-03)
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James Malcom: See the now longer P1385386 with 102 moves, and also P1385390, the extension to this. (2021-01-15)
A.Buchanan: I suggest you use the keywords “superseded by” and “length record” which are designed (together with “economy record”) to track evolution of challenges. A record keyword is removed when a problem is superseded. In my opinion, you were generous to have awarded S.Manikumar an “after” rather than a “version” - the interaction of the knights is the coolest part for me - did you originate that? (2021-01-16)
James Malcom: Yes, I shall do that tomorrow, along with some others.

The bishop tempo is an old an well-used mechanism, the only one I find suitable for this task. And yes, I came up with the duel of the knights. An "After" is deserved, both as gratitude and the clever dual elimination at the end, which mine detracts from. (2021-01-16)
James Malcom: See the now longer P1385390 with 102 moves, and also P1385386, the extension to this. (2021-01-15, hidden)
A.Buchanan: I suggest you use the keywords “superseded by” and “length record” which are designed (together with “economy record”) to track evolution of challenges. A record keyword is removed when a problem is superseded. In my opinion, you were generous to have awarded S.Manukumar an “after” rather than a “version” - the interaction of the knights is the coolest part for me - did you originate that? (2021-01-16, hidden) more ...
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Henrik Juel: C+ Popeye 4.79 (2021-01-04, hidden) more ...
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Henrik Juel: The motto is very apt
Why did you not frame the problem as a standard s#16, James? (2021-01-15)
James Malcom: It's probably because it was my first great leap at a long selfmate, and I didn't quite know all the conventions just yet. A color reversal should suffice for a C+ test. (2021-01-15)
SCHRECKE: C+, Gustav 4.1d, Brute Force (color reversal + rotation by 180 degrees) (2021-01-15)
A.Buchanan: In preserving this problem for future ages, I might tend to log the flipped version, and then record that the original was BTM, but up to you... :-) (2021-01-16)
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James Malcom: See the longer P1385386 and the earlier P1384834, of which this is an extension. (2021-01-15)
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Anton Baumann: C+ Gustav 4.2a (2023-12-08, hidden) more ...
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SCHRECKE: C+, popeye 4.85 (2021-03-22, hidden) more ...
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James Malcom: C+ by Jacobi with the restraints that wKe1 & wRa1 do not move. Here is the code.

English fors 8/8/p1p1p3/1bP1P2p/p1p4P/PkPp1p2/3P1P2/RNB1K3
option FirstToMove black
stip a=b8 pie whi ke1 ra1 addpieces
constraints Ke1(0..0) Ra1(0..0)
stip h006 (2022-06-12)
James Malcom: Meant EnglishN, a command that allows for avoidance of FEN editing with knight usage. (2022-06-12)
A.Buchanan: Jacobi constraints operate under the principle that castling doesn't count as a move for king or rook. I guess one can disable castling rights separately if one wanted? (Not relevant for this problem.)
Cheeky nit: can one remove wPf2? (2022-06-13)
James Malcom: I suppose that might be possible.

And yes, let me check if it can be removed. (2022-06-13)
Joost de Heer: The constraint is for the 'sub-position' after 8 moves, not for the h006 stipulation. It's to avoid searching lines like '1. Ra2 2. Ra1' where castling rights were lost along the way.

Another method to test would be
stip a=b1 pie whi ke1 ra1 addpieces
[repeat 13 times]
stip h001 (2022-06-13)
Joost de Heer: WHich also proves that f2 can indeed be removed (C+ in less than a second) (2022-06-13)
A.Buchanan: Thanks Joost for clarifications.
And how about also removing h-file pawns and adding bPf5? (2022-06-13)
James Malcom: That is illegal Andrew, requiring one capture too many. Nor does it change the move amount. (2022-06-13)
Joost de Heer: Black needs 7 captures, and 7 white pieces missing, so -Pf2, -Ph4, -Ph5, +bPf5 seems to work (and is C+ with the '13 a to b stipulations' test. (2022-06-13)
James Malcom: Ah, did not see that. Economical improvements are always nice--thanks both. (2022-06-13)
Joost de Heer: wBc1 to b2 is of course a correct h0014.5. (2022-06-14)
James Malcom: True, but for a new length record, longer than a measly ply, an entirely different setting may be needed. (2022-06-14)
Olaf Jenkner: I think, it's cooked.
Black can lose a tempo between a6 and a8 or between e8 and g6. (2022-06-14)
James Malcom: How so, Olaf? With White to move and wBc1-b2, there is no tempo to lose. Any delay by Black only causes further delay. (2022-06-15)
Olaf Jenkner: You are right, it's not a matter of tempos. (2022-06-15)
James Malcom: As always happens, I came across a 1997 problem with the same idea, albeit being mostly unique: P1000693 (2022-06-29)
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Henrik Juel: C+ Popeye 4.61
At first sight I thought that 1.h7 Lxc2 2.h8=DL thr. 3.DLxd4# would be a cook
but Black defends better by 1... dxc2!
Very impressive that the main variation is dual-free (2021-04-03)
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Henrik Juel: Nice control of the white batteries
Henrik Juel: C+ Popeye 4.61
Nice control of the white batteries (2021-04-10, hidden) more ...
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SCHRECKE: C+, Gustav 4.1d, Brute Force (2021-07-17)
Henrik Juel: C+ Popeye 4.61
1.f8=D g5 2.Tg8 Kh1 3.Dh6+ Kg1 4.Dxg5 Kh1 5.Dh4+ Kg1 6.Dxg3 Kh1 7.Th8+ Kg1 8.Dh2#
1.f8=S g5 2.Sh7 Kh1 3.Sxg5+ Kg1 4.Sh3+ Kh1 5.Sxf2+ Kg1 6.Sh3+ Kh1 7.Sg5+ Kg1 8.Sxf3#
Two very different solutions (2021-07-17)
James Malcom: See P1401781 for an improvement. (2022-06-12)
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SCHRECKE: C+, Gustav 4.2a, Brute Force (2022-04-20, hidden) more ...
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Henrik Juel: C+ Popeye 4.61 (2021-12-26)
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Henrik Juel: C+ Popeye 4.61, except for the mate dual after 3... Tc8 (2021-12-26)
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SCHRECKE: Die Idee ist als Miniatur darstellbar!
W: Kh4,Ta1,Ld1,Sg1 (4) - S: Kh2,Be2,Bf2 (3)
Lösung: 1.e1B Lf3 2.f:g1B Ta2# (2022-01-25)
SCHRECKE: C+, popeye 4.87, bedingung UWnur D T L S B (2022-01-25, hidden)
A.Buchanan: 8/8/8/8/7K/2R4P/4p1pk/3B4 (4+3)
C+ Popeye v4.87 1. e1=B Lf3 2. g1=B Tc2# (2022-01-26, hidden)
A.Buchanan: b7/8/4p3/6p1/1R4Kp/2P4P/3ppp1k/r1BB4 h#3 (5+9)
C+ Popeye v4.87 1. e1=B Lf3 2. d1=B Le3 3. f1=B Tb2#
No doubt can be done a bit more economically: have at it! (2022-01-26, hidden)
A.Buchanan: b7/8/1R2p2b/8/6Kp/7P/3ppp1k/r1BB4 h#3 (5+9)
C+ Popeye v4.87 1. e1=B Lf3 2. d1=B Le3 3. f1=B Tb2#
No doubt can be done a bit more economically: have at it! (2022-01-26, hidden)
A.Buchanan: b7/8/1R2q1n1/5n2/6K1/8/3ppp1k/r1BB4 (4+9)
C+ Popeye v4.87 1. e1=B Lf3 2. d1=B Le3 3. f1=B Tb2#
No doubt can be done a bit more economically: have at it! (2022-01-26, hidden)
A.Buchanan: b7/8/1R2q1n1/5n2/6K1/8/3ppp1k/r1BB4 (4+8)
C+ Popeye v4.87 1. e1=B Lf3 2. d1=B Le3 3. f1=B Tb2#
No doubt can be done a bit more economically: have at it! (2022-01-26, hidden)
A.Buchanan: b7/8/1R1brp2/8/7K/8/3ppp1k/r1BB4 (4+9)
C+ Popeye v4.87 1. e1=B Lf3 2. d1=B Le3 3. f1=B Tb2#
Can it be done more economically? Have at it! (2022-01-26, hidden)
A.Buchanan: 8/8/1Rbbq3/8/7K/8/3ppp1k/r1BB4 (4+8) h#3
C+ Popeye v4.87 1. e1=B Lf3 2. d1=B Le3 3. f1=B Tb2#
Meredith (2022-01-26, hidden)
A.Buchanan: Black moves open 6 lines, while if I replace sLd6 with sTf6, White moves close 3 lines. That lavish substitution seems worthwhile, yes? (2022-01-26, hidden)
A.Buchanan: 8/8/8/8/4R2K/6P1/4p1pk/7B h#2 (4+3)
C+ Popeye v4.87 1. g1=B Lf3 2. e1=B Tc2#
with tempo as the sole motivation for the 2nd promotion! (2022-01-26, hidden) more ...
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AB: economy record for 2 Dummy Pawns in h#. Miniature. Aimless promotion.
Henrik Juel: wPg3 prevents cooks like 1.Kg1 Kg3 2.e1=DTLSB Txe1# (2022-01-27)
Henrik Juel: C+ Popeye 4.79 (2022-01-27, hidden)
Henrik Juel: 1.g1=B Lf3 2.e1=B Te2# (2022-01-27, hidden) more ...
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Yuri Bilokin: you can see 1...gxh3 2.a5 h4 3.a4 h5 4.a3 h6 5.a2 h7 6.a1=R h8=Q 7.Rb1 Qc3# (2022-06-12)
SCHRECKE: C+, Gustav 4.2a, Brute Force (2022-02-19, hidden) more ...
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James Malcom: I had a thought looking at this again. Does n7/1P2P3/Q3P3/1r6/N1k1KP2/Pr6/B2p1p2/n7 work to save another piece? (2022-04-02)
A.Buchanan: James, yes your version does save another unit for your lovely idea. Beyond this, a version n7/1P2P3/Q7/Br6/2kPKP2/1r6/B2p1p2/n7 saves another unit, and forces a unique order on the Black promotions too. To avoid distracting unachievable threats, set NoThreat as well as the usual NoShortVariations. Your composition has driven me finally to report a long-standing Olive bug that cruelly punishes we Dummy Pawn enthusiasts: https://github.com/dturevski/olive-gui/issues/54. (2022-04-03)
James Malcom: Thanks for the verification and shaving off a unit, Andrew. (2022-04-03)
Henrik Juel: C+ Popeye 4.87 (2022-04-02, hidden) more ...
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Henrik Juel: C+ Popeye 4.61 (2022-06-11)
Henrik Juel: Hint
1.f8=DLS (2022-06-11)
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James Malcom: To my knowledge, the (dualless) length record for consecutive checks in the #n. (2023-06-16)
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Henrik Juel: mate trial in first variation
9.Sxf5+ Kh5 10.Sxg7,Sg3,Th4# (2022-06-26)
Jacques Rotenberg: If you really want a legal diagramme, you can begin after the key of P1298074, black to play, it will be legal and the longest sequence of checks (2022-06-30)
Jacques Rotenberg: ...doing so is not really enough ... no last move!
a tricky way would be - from diag P1298074 : - f5, -e7, + white knight f6 with 20 checks ahead + 2 retro checks ! (2022-07-01)
Jacques Rotenberg: ...not good either (2022-07-05)
Jacques Rotenberg: btw, I don't agree that my name will be as author of this diagram.
I am author of P1298074 not of this. (2022-07-08)
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SCHRECKE: C+, Gustav 4.2a, Brute Force (2022-06-30)
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Henrik Juel: Popeye 4.61 with 'opt thr 1' found no flaws
Congratulations, James (2022-10-08)
msterkowiec: Strange, I seem to see #12 here ( kB1N4/2P5/8/2pRP2n/2P1P1R1/bBK2p2/pp1Ppppp/n4Q2 ) with 1.R:c5 for example like this: 1... b1N+ 2. Q:b1 ab1N+ 3. Kd4 N:b3+ 4. Kd5 Nc3+ 5. dc3 Nf6+ 6. ef6 f1Q/e1Q 7.c8Q etc. (2022-10-09)
SCHRECKE: Ja, NL in 12 Zügen: 1. Txc5 (Gustav 4.2b) (2022-10-09)
James Malcom: Thank you Henrik.

Strange, this usually never happens to me. This is indeed the position I sent. Yet I know I tested for Txc5. I made a mistake, but I forget how. In any case, Td5-d7 seems to fix the issue? (2022-10-09)
msterkowiec: Yes, in position #16 kB1N4/2PR4/8/2p1P2n/2P1P1R1/bBK2p2/pp1Ppppp/n4Q2 John Galt 4.6 finds no other solution but 1.c8Q.

BTW: here you can find a link to it: http://szachowe.pl/viewtopic.php?f=18&p=118120&sid=6e44d27ffcffe4cf867c23001ab11773#p118120

I write to be super fast and I believe it can save quite much time of chess composers...
(It's not a popular piece of software and Windows pops out quite many warnings about it, anyway it's enough to trust your antivirus) (2022-10-12)
Olaf Jenkner: The position Td7 is C+ (Gustav 4.2 b)
There are three full length variations. (2022-10-13)
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Henrik Juel: Very impressive, James
Black needs to post a promoted rook on g1 again and again to prevent the threat 2.Sg5+ T7xg5#
A promoted queen does not work, because of 2... Dxg5#
You should label it C+, despite the possible duals in short variations, I think (2023-06-03)
James Malcom: Thanks.
Labeled as intended, now.
This task took over two years to realize: http://superproblem.ru/archive/Labor/Malcom-S.html (2023-06-03)
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SCHRECKE: Here is a s#7 with 4 dummy pawns: QnRn1B1K/P1P1P1P1/k1N5/3p2p1/2PPB1P1/8/4p1pR/4Nbrr
1. axb8=B+! Kb6 2. Da7+ Kxc6 3. cxd8=B+ Kd6 4. e8=B+ Ke6 5. Lxd5+ Kf6 6. Le7+ Kg6 7. g8=B Txh2#
Who makes it better? (2023-06-07)
James Malcom: Wonderfully done. I had an illegal scheme for four I never realized, but now it is done: 1RrRq1BK/pP1P1PP1/Pk2N1N1/p3p1p1/p2PP1P1/3Q3p/6pr/6Bb

I see no improvements to yours, yet. (2023-06-07)
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SCHRECKE: Dear James, the authors should be Malcolm/Schreckenbach. (2023-07-11)
James Malcom: Done. (2023-07-12)
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SCHRECKE: Have a look at this: R4q1k/pPP3R1/rp3PKn/p5PQ/P7/8/8/8
s#2, 1. f7! - 6(!) dummy promotions (2023-07-28)
SCHRECKE: In my work a black rook on f8 is better! (2023-07-28)
A.Buchanan: Yes this is a great improvement. I can't see how one might get a 7th (2023-07-28)
SCHRECKE: C+, popeye 4.87
1. Tg8! (Zugzwang)
1. ... Txg8 2. hxg8B
1. ... Tf8 2. gxf8B
1. ... Td8 2. cxd8B (2023-07-28, hidden) more ...
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SCHRECKE: C+, popeye 4.87
1. Da6! droht 2. f4 h1=D,L#
1. ... h1=B! 2. bxa8=B! g4!
3. f4 droht 4. Lxd2 droht 5. Le1 fxe1D,T#
3. ... f1=B! 4. e8=B! d1=B!
5. Le1 Sc2 6. Lb1 Te3# (2023-09-09)
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Henrik Juel: 1.b4 h5 2.b5 h4 3.b6 h3 4.b7 h2 5.b8=DP Lxg7# (2023-08-08, hidden) more ...
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Schade um das dualistische Matt. Im strengen Sinn also kein Rekord.
SCHRECKE: sTg8 gehört nach f8! (2023-08-18)
James Malcom: Fixed. (2023-08-18)
SCHRECKE: Der wSb6 ist überflüssig!! (2023-08-18)
James Malcom: That's a surprise. (2023-08-18)
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