How would queening the pawn win? Black would be in stalemate next move if he couldn't sac the piece of b6 next move, which is why a knight on c8 is necessary to begin with. Am I missing something?
Here, take a look:
Oh ok nevermind.
Actually I think I can make it work by placing a pawn on square a2:
Unless of course I'm mistaken, I'll have to check it when I get home from work this phone pgn editor sucks.
Stockfish was confused and thought it was 0.00 for a while when I plugged in the queen promotion in the first diagram, then saw the mate in 11 lol, but technically the knight is faster with m7, but you're right, everything should be the unique way to win/draw, not just a little faster!
what
Refer to diagram 418, we were discussing whether the puzzle could be improved by adding a 2nd underpromotion on move 1 instead of starting with a knight on c8. But it turns out a queen can also win, I haven't analyzed the most updated version though Inwill do that later today!
Good puzzles but the last one is iffy. By the rules of chess you can underpromote any pawn but what's the point when it's equal to or worse than the standard queen promotion? The Bishop promotion does not work and the moves given are wrong!
In some games, promotion to a queen can end in a draw by stalemate or because no moves really do anything. Rooks usually prevent stalemates, knights are used usually for forking and the bishops in used in very rare cases where the other pieces make it stalemate or doesn’t do anything in the position,
Refer to diagram 418, we were discussing whether the puzzle could be improved by adding a 2nd underpromotion on move 1 instead of starting with a knight on c8. But it turns out a queen can also win, I haven't analyzed the most updated version though Inwill do that later today!
The revised version works, so now it's a mate in 11 with 2 underpromotions.
White to move and mate in 11:
Because the a pawn blocks the rook, nice!
Here is a nice White to play and win study by Alexander Stavrietsky that requires an underpromotion to secure the victory for White:
Another underpromotion as the only way to secure the point, white to move and mate in 6:
I feel like that one could be modified to have more pawns and end up having multiple knight underpromotions similar to my previous one like this:
I was just trying to design one where the queen has multiple sacrifice options and the queen has to find the correct square so everything is timed perfectly, but haven't found a position that works yet with that!
I feel like that one could be modified to have more pawns and end up having multiple knight underpromotions similar to my previous one like this:
Even better.
Did somebody say multiple Knight underpromotions? 
White to move and mate in 7:
Did somebody say multiple Knight underpromotions?
White to move and mate in 7:
very impressive
I like how that one is so much more realistic than the still undefeated 8 knight promotions puzzle. It looks like a blitz game where white tried to ram the queenside with everything but got careless and let that e pawn through, or mouseslipped and forgot to to move the king to f1, but still managed to pull an obscure mate out of it lol
How would queening the pawn win? Black would be in stalemate next move if he couldn't sac the piece of b6 next move, which is why a knight on c8 is necessary to begin with. Am I missing something?