Is there a forced win for White or Black in the chess variant CastleChess? The rules are explained in this post on an obscure blog named “Cinquante signes”, although it is originally from chessvariants.com.
The rules are the same as the orthodox ones, but with two big differences.
White wins via checkmate or if Black can no longer castle queenside. If either the Black king or queenside rook move, of if the rook is captured, Black can no longer preform queenside castling, and thus they lose.
Black can win by giving mate or castling queenside.
The devil is in the details, and there are some questions on the blog that help give insight into whether or not it can be solved.
Q.(b): Is it easy for Black to castle long (and immediately win the game)?
Well, if White is not prudent, yes -in theory, 5 moves are enough for Black to win.
Q. (c): Are draws still possible?
Oh yes, if it's White turn to play for instance, and White is (a) not in Check (b) in check if it moves, the game is a draw (as in orthodox chess).
Q. (e): Do you have any strategic advice?
Yes-there are weaknesses in Black's position. White could focus on: the pawns a7, b7 and f7 for instance.
Q (f): And what about Black's defense?
This position is solid-and, in a few moves, Black might be able to castle long and win: put all Black pieces on their starting square, except 3 — the e7 pawn is on e6; the b8 Knight is on c6; the f8 Bishop is on b6.