Proof Game in 26.5 moves

PG in 26.5 moves
(position after White's 27th move; find the gamescore)

Why does black have 3 knights?

Originally posted by laedawg
Why does black have 3 knights?

Obviously he has "queened" a pawn.

Why on Earth would you choose a Knight over a Queen?

Did you notice White has three rooks? 😀
In a proof game the moves need only be legal - they do not have to make any sense as moves in an actual game.
Anyway, what would you play in this position (you are white and it's your turn):

And a set of little challenges (but don't forget BDP's problem!)
Find positions with minimal number of chessmen where:
1. Knight promotion is the only winning move;
2. Rook promotion is the only winning move;
3. Bishop promotion is the only winning move;
4. Knight promotion is the only drawing move (solution above);
5. Rook promotion is the only drawing move;
6. Bishop promotion is the only drawing move.
The best solutions I know of are as follows:
Challenge no. 1 - 4 pieces;
Challenge no. 2 - 3 pieces;
Challenge no. 3 - 5 pieces;
Challenge no. 4 - 4 pieces;
Challenge no. 5 - 7 pieces;
Challenge no. 6 - 6 pieces.
Can you find the positions?

Originally posted by David113
Did you notice White has three rooks? 😀
In a proof game the moves need only be legal - they do not have to make any sense as moves in an actual game.
Anyway, what would you play in this position (you are white and it's your turn):
[fen]4K3/r4P2/4k3/8/8/8/8/8[/fen]
And a set of little challenges (but don't forget BDP's problem!)
Find positions with min ...[text shortened]... ieces;
Challenge no. 5 - 7 pieces;
Challenge no. 6 - 6 pieces.
Can you find the positions?

f8=N+

Originally posted by David113

And a set of little challenges (but don't forget BDP's problem!)

Can you find the positions?[/b]

Here's the first three:

1. Knight promotion is the only winning move;
wKf5 Bg6 Pg7; bKh6. 1.g8N+!
2. Rook promotion is the only winning move;
wKa5 Pc7; bKa7. 1.c8R!
3. Bishop promotion is the only winning move;
wKb4 Nd5 Pb7; bKa6 Pa7. 1.b8B!

The queen was left off the list, because that task isn't possible with 3 units, and trivial with 4 units.

Originally posted by laedawg
Why does black have 3 knights?

Probably for the same reason White has three Rooks.

Originally posted by David113

And a set of little challenges (but don't forget BDP's problem!)
Find positions with minimal number of chessmen where:

4. Knight promotion is the only drawing move (solution above);

Can you find the positions?

Seems there are multiple solutions for this one.

wKh5 Pe7; bKf6 Qg7

Menaced with ...Qg5#, White's only escape is 1.e8N+, winning the Queen and drawing.

Originally posted by David113

And a set of little challenges (but don't forget BDP's problem!)
Find positions with minimal number of chessmen where:

5. Rook promotion is the only drawing move;

The best solutions I know of are as follows:
Challenge no. 5 - 7 pieces;

I can beat this by 2 units.

wKc1 Ph7; bKa1 Pa2h2.

Of course, White can win (1.h8Q#, 1.h8B# ) or lose (1.h8N, 1.K~) but only 1.h8R h1Q+ etc. draws.

Originally posted by David113

And a set of little challenges (but don't forget BDP's problem!)
Find positions with minimal number of chessmen where:
6. Bishop promotion is the only drawing move.

The best solutions I know of are as follows:
Challenge no. 6 - 6 pieces.

Using my idea from challenge #5, I can do this one with a mere 4 units.

wKc2 Pa7; bKa1 Ph2.

1.a8B is the only drawing move.

When I wrote "move X is the only drawing move" I meant that all other moves are losing.

Originally posted by David113
When I wrote "move X is the only drawing move" I meant that all other moves are losing.

As my examples show, the stip must explicitly state this (or my examples become cooks).

Originally posted by BigDoggProblem
3. Bishop promotion is the only winning move;
wKb4 Nd5 Pb7; bKa6 Pa7. 1.b8B!

Wrong.

White mates in 103 (!) by 1.b8N.

Originally posted by David113
Wrong.

White mates in 103 (!) by 1.b8N.

Prove it.