I noticed the option for pawn promotion. This is consistant with the
rules that I know. However, I wonder is there any reason to chose
anything other than a queen or a knight? The knight might be a
choice in a certain check or checkmate moves, but can't the queen do
everything else? Just a trivia question. Daniel
A choice of Queen may result in stalemate if it means a diagonal
check that the King cannot move out of or block. Strange things, but I
have "heard" that a promoted pawn does not automatically put king in
check ... I'll have to verify rules, because both sides of the equation
have validity.
crythias, I'm afraid your post does not make much sense! If the
promotion of a pawn puts the king in check which it cannot move out
of or which cannot be blocked (or the checking piece cannot be
captured) then it is checkmate just the same as normal. Also a
promoted pawn will only put the king in check if the piece to which it is
promoted is threatening to capture the king or if it causes a
discovered check from another piece - again just the same as normal.
However you are correct that promoting to a queen may result in
stalemate.
Please see my other post for an example of under promotion.
Dant, here is an example of when it is beneficial to under promote a
pawn. Take the simple position with a white king on c2, a white pawn
on c7, a black king on a1 and a black rook on d4 with white to move.
If white plays c8=Q black plays Rc4+ and draws as Qxc4 is stalemate.
However if white plays c8=R black loses as after Ra4 (to prevent Ra8
mate) white plays Kb3 and wins because of the double threats of Kxa4
and Rc1 mate.
