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Escaping a double check

The answer to Is it possible to block a double check? says

Moving the king is the only way to escape a double check. There is no possible other move that will block both checks.

But in the following situation, is it allowed for Black to escape by taking the Rook (placing White in check) and forcing a sacrifice of the Queen? If not, why not?

Black to move. Never mind how it got to this position, it's for illustration.

enter image description here

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    "Never mind how it got to this position, it's for illustration" -- a bit too glib. You position doesn't work, but if it did it would be irrelevant since there is no legal way that it could arise. Mar 5 at 12:56
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    The point of my comment is that when trying to understand the rules of chess, it isn't helpful to wonder how they apply to positions which can never arise. When crafting a position, why not do the extra work to make sure that it can arise via a legal sequence of moves? Mar 5 at 13:06
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    Is the starting position legal? Looks like it requires an illegal move to reach. From the first position, Black is checkmated and does not get a move. Mar 5 at 14:38
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    For future visitors, this question could be greatly improved by using a valid position. The OP's current 3 position sequence is illegal. Mar 5 at 17:32
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    An important thing to remember when thinking about chess situations: if you capture the opposing king, you win.
    – Mark
    Mar 6 at 5:15

3 Answers 3

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Not allowed, no.

White gives two checks (hence double), and meeting one isn't enough. After blacks reply Qxe8+, blacks king is still in check which makes Qxe8+ an illegal move.

Black is thus checkmated in your position.

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  • A similar question on Quora (I don't have an account) says "... It may be possible to play a move that blocks the attack on your King while giving check to the opponent's King, but it is very seldom you'll have the opportunity to do that..." Mar 5 at 11:16
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    @WeatherVane that's possible in single check situations but not double checks. If your king is being attacked by another piece after you make your move, that's an illegal move.
    – llama
    Mar 5 at 23:48
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    @WeatherVane: If it helps, you can think of it as "whoever captures the enemy king first wins" (we just end the game before that actually happens). In your second image above, it's white's turn so he can play Nxa8 before black can play Qxe1. Mar 6 at 0:20
  • Is there a move (in other double checks, not the above one) that blocks both checks, and puts the opponent in check? That would be very "call an ambulance... but not for me".
    – stevec
    Mar 6 at 2:15
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    @stevec that could be another question, but it's not possible to block a double check because if the checks are blockable, they have to be along different directions (pick two of rank, file, diagonal) so one square can't block both. It's pretty easy to construct something where you move out of double check and put the opponent in check though: Rd4+ for white here would be bad for that reason lichess.org/analysis/8/8/1r1k3K/8/5R2/6B1/8/8_w_-_-_0_1#0
    – llama
    Mar 6 at 3:04
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For this kind of questions, if you have doubts, just play chess with the goal of capturing the enemy king. The first player to capture the enemy king wins. This isn't the official rule, but it's effectively the same in almost all situations I'm aware of (it doesn't work for stalemate).

So after 1...Qxe8+, White wins with 2. Nxa8. It doesn't matter that Black also threatens to capture White's king with 2...Qxe1, since White has already won.

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A legal way to get into the same kind of situation:

enter image description here enter image description here

But as others have posted: It is illegal to make a move that places or leaves one's king in check.

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    Exactly. Black has no move after 1. Rc8#. The game is over. Mar 5 at 18:59

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