OK, so “announced move chess” didn’t work out. Here is a revised version:
White announces his first move, but does not play a move.
Black announces his first move, but does not play a move.
On each subsequent move, each player must either play his previously announced move, or play a move that makes his opponent’s next (and already announced) move illegal. A player who does the latter immediately wins the game. Otherwise, when a player plays a move, he must also announce his next move.
Note that an announced move is defined solely by its stated (or implied) departure square and arrival square. If the status of the arrival square changes unexpectedly, it does not change the move. For example, if a player announces Nf3xg5, but the piece on g5 isn’t there anymore, then Nf3-g5 still satisfies the requirement to play the previously announced move.
Does this version make Bill Brock’s 2.Qh5 a dangerous foray? And, if so, for which player is it dangerous?
The center counter could never be played (white’s announced 2. ed is negated by black winning by playing e5 instead of d5. There would be a number of moves that would become unplayable, such as 1. e4 (announce Qh5) e5 (announce g6) 2. Qh5 (announce Qxe5+) Qg5 (winning by making Qxe5 impossible).
e4 (announced Qh5) e5 (announced Nc6) 2. Qh5 (announced Nc3 wins) since Nc3 cannot be stopped and …Nc6 allows either Qxf7 (countered by black announcing Kxf7) or Qxe5 (countered by black announing Nxe5 or Be7 or Qe7). Black can’t announce both. Black would have had to announce g6 instead of Nc6 and White could still announce Nc3 in the sublime confidence that Black cannot announce capturing a queen that would run away instead of being captured and thus has to announce either Be7 or Qe7 so that such a move could still be made after Qxe5.
hmm… if white announces Qg6 instead of Nc3 then he captures the pawn safely because the pawn recaptures cannot be announced. Eventually white should be able to announce Qxf7 and black would need to announce a retreat instead of a recapture.
e4 (announced Bc4) d6 (announced Be6) seems to hold, because if 2. Bc4 (announced Bd5) Be6 (announced Bd5) 3. Bd5 (announced exd5) Black wins with Bd7, or any bishop move other than Bxd5. That’s good, because it isn’t much of a game if White has a forced win.
I’ve just realized that we (or I) have ignored one of Bill’s rules: on the first move, each player is supposed to announce a move without playing it. So after (announced e4) (announced Nf6) White isn’t likely to play 1. e4 (announced Qh5).
Oops, you’re right. Instead of 2…Be6 (announced Bd5) Black should announce some other move, like Nf6. Then White can’t play 3. Bd5 (announced Be6) because 3…Bxd5 would make 4. Be6 illegal/impossible. Neither bishop can capture the other.
This game is very complicated, and it could be a good one if Black can survive White’s initial attack.
Double king pawns a probably a forced win for white.
after 0. (announced e4) (announced e5) 1. e4 (announced Qh5) e5 (announced g6 since any other move would allow Qxf7 and taking that into account would fail to Qd1)
2. Qh5 (announced Qg6) g6 (announced Qe7 since any recapture on g6 or e5 would lose to Qd1, anything that doesn’t block on e7 would lose to Qxe5, and Be7 has issues that will be seen shortly) 3. Qxg6 (announced Nc3) Qe7 (announced Kd8 - any other move other than a recapture on f7 loses to Qxf7 and an announced recapture loses to Nc3)
variation one
4. Nc3 (announced Nd5) Kd8 (announced Nc6 - Na6, Nc6 and Qf6 are the only three moves that cannot be rendered illegal by moving white’s queen on the third rank or taking on f7 or g8, announced …Qf6 is variation two)
5. Nd5 (announced Ne7) Nc6 (announced b6 since any other announced move can be rendered illegal) 6. Nxe7 (announced Nxf5) b6 (find a move to announce that is legal after the possible Ne7xc6+ and Qxf7 and Qxg8)
variation two
4. Nc3 (announced Nd5) Kd8 (announced Qf6) 5. Nd5 (announced Nf3 - to stop the Qxf2+ mess) Qf6 (and now what can be announced that will still be legal after Qxg8 and Qxf7 and Qf6)
Double e-pawn revisited.
0 (announce e5) (announce e5) 1. e4 (announce Qh5) e5 (announce Qf6) 2. Qh5 (announce Nf3) Qf6 (announce Kd8) 3. Nf3 (announce Qg6) Kd8 (announce Ne7) 4. Qg6 (announce Bb5). Ne7 and then figure out an announcement (I can only see b6, d6 or using the b8 knight and having it subsequently frozen by the b5 bishop - announcing Ng6 fails to Qxf6).
Yikes!! I guess this variation may stay alive, at least long enough for a couple more pages of posts. It seems similar to Half Bughouse in one respect, namely, that white has a strong advantage, bordering on a forced win.
I can’t wait to see some endgame problems, especially K+Q vs K. When you propose an endgame problem in this game, remember you must specify not only the positions of all the pieces and whose move it is, but also each player’s immediately previous move announcement.
And then there is also the possibility of some good retrograde analysis problems.
Black’s attempt to win White’s queen by playing Kc8 followed by Ng6 doesn’t seem to work: 4…Ne7 (announce d6) 5. Bb5 (announce b3) d6 (announce Bd7) 6. b3 (announce Ba3) Bd7 (announce Nc6) 7. Ba3 (announce Nc3) Nc6 (announce Kc8) 8. Nc3 (announce Bc6) and if 8…Kc8 (announce Ng6) 9. Bxc6 (announce Bd6) Nxg6 and anything Black announces will lose, e.g. (announce Qf3) 10. Bxd6 (announce Nd5) and Qxf3 is illegal because of 11. Bxb7+ or 11. Bd7+.
