user30297: [FEN "6k1/rp3ppq/p2p4/1p1Pr1nQ/1P2P3/4R1N1/P1B2P2/4R1K1 b - - 0 1"]

1... Nh3+ 2. Qxh3 (2. Kh2 Rxh5) 2... Qxh3

Black to move.
After Nh3+ white can move the king or take with the queen. Either way black can win the queen.
How is this tactic called?

user25458: I think it is a discovered attack. Normally at a discovered attack, you do give a check to the king, eventually a double check. Here what is different is that you do a check to the king but you discover an attack on the queen, not also towards the king.

user13433: It's not uncommon that a tactical sequence makes use of more than one general pattern.
Here, we have a double attack where one of these attacks is a discovered one (the rook on the queen) and the other is a decoy (the knight check lures the queen to a square where it will be undefended).

user15221: It's a discovered attack with check (the rook attacking the queen is the discovered attack, the check is the discovering move). As the discovering move is also an attack, this gives rise to a double attack. The check must be answered, so the queen takes the knight even though it is protected. This could also be considered a desperado from White's point of view; the queen can't be saved, so White might as well take the knight.

30297: <pre><code>[FEN &quot;6k1/rp3ppq/p2p4/1p1Pr1nQ/1P2P3/4R1N1/P1B2P2/4R1K1 b - - 0 1&quot;]

1... Nh3+ 2. Qxh3 (2. Kh2 Rxh5) 2... Qxh3
</code></pre>
<p>Black to move.</p>
<p>After Nh3+ white can move the king or take with the queen. Either way black can win the queen.</p>
<p>How is this tactic called?</p>
 25458: <p>I think it is a discovered attack. Normally at a discovered attack, you do give a check to the king, eventually a double check. Here what is different is that you do a check to the king but you discover an attack on the queen, not also towards the king.</p>
 13433: <p>It's not uncommon that a tactical sequence makes use of more than one general pattern.</p>
<p>Here, we have a <strong>double attack</strong> where one of these attacks is a <strong>discovered</strong> one (the rook on the queen) and the other is a <strong>decoy</strong> (the knight check lures the queen to a square where it will be undefended).</p>
 15221: <p>It's a <strong>discovered attack</strong> with check (the rook attacking the queen is the discovered attack, the check is the discovering move). As the discovering move is also an attack, this gives rise to a <strong>double attack</strong>. The check must be answered, so the queen takes the knight even though it is protected. This could also be considered a <a href="https://en.wikipedia.org/wiki/Desperado_(chess)" rel="noreferrer"><strong>desperado</strong></a> from White's point of view; the queen can't be saved, so White might as well take the knight.</p>
