The Christmas Prize Puzzles proved popular with readers with over 100 visits on the website. On the other hand I received only a small number of entries and messages regarding the puzzles with the general consensus being that they were very hard. That was my intention but perhaps I made them a bit too hard!
The winner of the prize was Allan Pleasants (Weymouth and Wimborne) with 5 puzzles solved. An honourable mention goes to Richard Ormesher (Ringwood) with 4 puzzles solved, very impressively completed all in one afternoon.
Between them they solved 6 of the puzzles with only No. 7 remaining uncracked, with both Allan and Richard, very understandably, saying that they had run out of time!
Peter Anderson 6/1/2023
Solutions
Prize Puzzle 1
White to play and win. Strictly there is more than one solution to this – any is fine!
The winning method is to lure the Black pawns forward one at a time and capture them without stalemating Black. The tidiest method is shown in the mainline with other winning moves given as sidelines.
1.f3 (or 1.f4 is equally good) 1…exf3 2.Kf1 f2 3.e4 dxe4 4.Kxf2 e3+ 5.Ke1 e2 6.d5 cxd5 7.Kxe2 (7.Kd2) (7.Kf2) 7…d4 8.Kd2 (8.c6) 8… d3 9.c6 (9.Kd1) 9…bxc6 10.Kxd3 Kb7 11.Kc4 Ka8 12.Kc5 Kb7 13.a8=Q+ Kxa8 14.Kxc6 Kb8 15.b7 Ka7 16.Kc7 +-
Prize Puzzle 2
Below is the position in a game of chess after White’s 7th move (from the normal starting position, not Fischer Random). However, as you can see, whilst the colours of the pieces are identified, which piece is which is not.
How did the game go?
The game went 1.h4 Nh6 2.h5 Nf5 3.h6 Nd4 4.hxg7 h6 5.g8=Q Rh7 6.Qg3 Bg7 7.Qh2
Prize Puzzle 3
White to play and win. At first sight the position is completely blocked and therefore drawn – can you find the way to unlock it? (Please note Black has not just played g5 and so White cannot play hxg6 in this position).
What is obvious about this position is that if White can get his knight to f5 he or she will be winning as the h6 pawn will drop and then White can mop up more of Black’s pawns. The question is how to get the knight to f5. This requires some clever re-routing of the knight, offering it up as a passive sacrifice on both sides of the board along the way, in both cases with the white king in attendance on that side of the board. In either case if the knight is taken then the resulting pawn ending is won for White. Here is the knight’s route.
The exact moves depend on exactly what Black does but here is a typical mainline and the two key side variations where Black captures the knight.
1.Nc1 Kd7 2.Ne2 Kc6 3.Ng1 Kd6 4.Nh3 Ke6 5.Nf2 Kd6 6.Nd1 Kd7 7.Nb2 Kd6 8.Na4 Kc6 9.Kc2 losing a tempo to gain access to b6 for the knight) 9…Kd6 10.Nb6 Ke6 11.Nd5 Kf7 12.Nc7 Ke7 13.Nb5 Kd7 14.Kb2 Kc6 15.Na3 Kd7 (15…bxa3+ 16.Kxa3 Kb6 17.b4 winning) 16.Nc2 Ke7 17.Ne1 Kf7 18.Ng2 Kf6 19.Kc2 Kg7 20.Kd2 Kf7 21.Ke2 Kg7 22.Kf2 Kf7 23.Kg1 Kf6 24.Kh2 Kf7 25.Kh3 Kg7 26.Nh4 Kh7 (26…gxh4 27.Kxh4 Kf6 28.g5+ hxg5+ 29.Kg4 winning) 27.Nf5 winning
You can see it with more detail on this interactive board.
Prize Puzzle 4
It is Black to play in this position. What were the previous 2 moves of each player?
As it is Black to move White’s last move must have been a king move. The key to solving this is working out where the white king was on the previous move and how that could be legal… and then working out how the position before that could be legal. Here’s the logic…
Obviously the white king cannot have come from d3, d4, e4 or f4 as it would have been next to the black king. If it came from d5, e6 or f6 it would have been in a double check that is impossible to construct. However, if it was on f5 there could have been a double check that arose from an e.p. capture. So it must have been Black to move in a position something like the one below, with White having just played g4 (from g2) and Black replying fxg3+.
However, consider the position with the pawn on g2. The bishop cannot have moved to h3 to give check. Therefore the check must be a discovered check. As the queen and rook could not have moved from g4 to give the discovered check we can conclude it must have been a piece that is no longer on the board. Therefore, the white king must have captured it on e5 and hence it must have been a knight. So the original position was…
… and the last two moves were 1…Ne5+ 2.g4 fxg3+ 3.Kxe5
Prize Puzzle 5
Helpmate in 3. There are two solutions – please find both.
Just a reminder that in helpmates Black moves first and is trying to help White to checkmate Black. So in this puzzle Black plays 3 moves and White plays 3 moves, alternating as usual, with Black going first and White giving mate on his third move.
With only six pieces on the board, how hard can this be ?!
The two solutions use a block of the long diagonal by the white rook to allow black king to d5 and then a discovered checkmate with the rook controlling the sixth rank. One of the checkmates is from the top and one from the bottom. The two solutions are…
1…Bf8 2.Rb2 Bc5 3.Rb7 Kd5 4.Rb6 mate
1…Rc5 2.Bh1 Be5 3.Rg2 Kd5 4.Rg6 mate
Prize Puzzle 6
From the position after White has played 1.e4, Black delivers checkmate on his/her 5th move with NxR (knight captures rook). How does the game go? (Strictly there are two solutions with slightly different move orders).
1.e4 Nf6 2.Qe2 Nxe4 3.f3 Ng3 4.Qxe7+ Qxe7+ 5.Kf2 Nxh1#
or
1.e4 Nf6 2.f3 Nxe4 3.Qe2 Ng3 4.Qxe7+ Qxe7+ 5.Kf2 Nxh1#
Prize Puzzle 7
There are two exceptions to the normal rules of chess here:
- White does not have a king
- The bishop is immobilised but it can still give check. The bishop cannot move from a1 but the king cannot go on the a1-h8 diagonal unless it can capture the bishop.
White to play and mate in 13.
White needs to get the queen and king a knight’s move apart with Black to move in order to drive the king towards a corner. The solution starts with 1.Qc6+ and then:
- if Black plays 1…Ka7 White drives the king to a2 or b1 and delivers mate with Qb2#
- else if Black plays 1…Kb8 White drives the king to g8 or h7 and delivers mate with Qg7#
Here are a few sample lines. There are some alternative moves for White at some points that also deliver mate in 13 but the overall method is the same.
1.Qc6+ Ka7 2.Qc8 Kb6 3.Qd7 Ka6 4.Qc7 Kb5 5.Qd6 Kc4 (This is position A)
6.Qe5 Kd3 7.Qf4 Ke2 8.Qg3 Kd2 (8…Kf1 9.Qh2 Ke1 10.Qg2 Kd1 11.Qf2 Kc1 12.Qe2 Kb1 13.Qb2 mate) 9.Qf3 Kc2 10.Qe3 Kd1 11.Qf2 Kc1 12.Qe2 Kb1 13.Qb2 mate
1.Qc6+ Ka7 2.Qc8 Kb6 3.Qd7 Ka6 4.Qc7 Kb5 5.Qd6 Ka5 (This is Position B)
6.Qc6 Kb4 7.Qd5 Ka4 8.Qc5 Kb3 9.Qd4 Ka3 10.Qb2+ Ka4 11.Qb6 Ka3 12.Qb5 Ka2 13.Qb2 mate
1.Qc6+ Ka7 2.Qc8 Kb6 3.Qd7 Kc5 4.Qe6 Kb5 5.Qd6 Kc4 transposes to Position A whilst 5…Ka5 transposes to Position B.
1.Qc6+ Kb8 2.Qa6 Kc7 3.Qb5 Kd6 (3…Kc8 4.Qb6 Kd7 5.Qc5 Kd8 transposes to Position C, whilst 3…Kc8 4.Qb6 Kd7 5.Qc5 Ke6 transposes to Position D) 4.Qc4 Kd7 5.Qc5 Kd8
(This is Position C) 6.Qc6 Ke7 7.Qd5 Ke8 8.Qd6 Kf7 9.Qe5 Kg6 10.Qf4 Kh5 11.Qg3 Kh6 12.Qg4 Kh7 13.Qg7 mate
1.Qc6+ Kb8 2.Qa6 Kc7 3.Qb5 Kd6 4.Qc4 Kd7 5.Qc5 Ke6
(This is Position D) 6.Qd4 Kf5 (6…Ke7 7.Qd5 Ke8 8.Qd6 Kf7 9.Qe5 Kf8 (9…Kg6 10.Qf4 Kh5 11.Qg3 Kh6 12.Qg4 Kh7 13.Qg7 mate) 10.Qg7+ Ke8 11.Qc7 Kf8 12.Qd7 Kg8 13.Qg7 mate) 7.Qe3 Kg4 8.Qf2 Kg5 9.Qf3 Kg6 (9…Kh4 10.Qg2 etc) 10.Qf4 Kh5 11.Qg3 Kh6 12.Qg4 Kh7 13.Qg7 mate.
