Project approval after AI review on 2 November 2026. Human proofreading is still pending.
Lesson 14
A move opens an attack
- What you will learn
- You move a piece out of the way so that another gives check, and gain material at the same time.
- What you should already know
- What a pin is
- Lesson 13: A piece that cannot move
Time: about 5 minutes
Thinking questions in this lesson
You can ask yourself these thinking questions in any position. They help you find a good move.
- Which piece could be better placed?
Step 1 of 7
Look first
Look along the e-file: your queen, your knight and the black king.
Tap the white piece that can move away to open your queen’s path to the king.
Arrow keys move the focus across the squares. Enter or Space marks a square or removes the mark.
Choose a square from a list
Position as a list
White
- King e1
- Queen e2
- Rook a1
- Rook h1
- Bishop c1
- Bishop f1
- Knight b1
- Knight e5
- Pawn a2
- Pawn b2
- Pawn c2
- Pawn d2
- Pawn f2
- Pawn g2
- Pawn h2
Black
- King e8
- Queen d8
- Rook a8
- Rook h8
- Bishop c8
- Bishop f8
- Knight b8
- Knight f6
- Pawn a7
- Pawn b7
- Pawn c7
- Pawn d7
- Pawn f7
- Pawn g7
- Pawn h7
Step 2 of 7
Decide
Which piece could be better placed? Here it is the knight between the queen and king.
Where should the knight move to uncover the check?
Arrow keys move the focus across the squares. Enter or Space selects a piece and moves it to a highlighted square. Escape cancels the selection.
Position as a list
White
- King e1
- Queen e2
- Rook a1
- Rook h1
- Bishop c1
- Bishop f1
- Knight b1
- Knight e5
- Pawn a2
- Pawn b2
- Pawn c2
- Pawn d2
- Pawn f2
- Pawn g2
- Pawn h2
Black
- King e8
- Queen d8
- Rook a8
- Rook h8
- Bishop c8
- Bishop f8
- Knight b8
- Knight f6
- Pawn a7
- Pawn b7
- Pawn c7
- Pawn d7
- Pawn f7
- Pawn g7
- Pawn h7
Step 3 of 7
Try it
Move the knight out of the way so that it attacks Black’s strongest piece.
Arrow keys move the focus across the squares. Enter or Space selects a piece and moves it to a highlighted square. Escape cancels the selection.
Choose a move from a list
Position as a list
White
- King e1
- Queen e2
- Rook a1
- Rook h1
- Bishop c1
- Bishop f1
- Knight b1
- Knight e5
- Pawn a2
- Pawn b2
- Pawn c2
- Pawn d2
- Pawn f2
- Pawn g2
- Pawn h2
Black
- King e8
- Queen d8
- Rook a8
- Rook h8
- Bishop c8
- Bishop f8
- Knight b8
- Knight f6
- Pawn a7
- Pawn b7
- Pawn c7
- Pawn d7
- Pawn f7
- Pawn g7
- Pawn h7
Step 4 of 7
Two pieces at once
A game from Nimzowitsch’s chapter: Réti – Tartakower, Vienna 1910. Black has just captured the white queen on d8.
Give check with two pieces at the same time.
Arrow keys move the focus across the squares. Enter or Space selects a piece and moves it to a highlighted square. Escape cancels the selection.
Choose a move from a list
Position as a list
White
- King c1
- Rook d1
- Rook h1
- Bishop d2
- Bishop f1
- Knight g1
- Pawn a2
- Pawn b2
- Pawn c2
- Pawn f2
- Pawn g2
- Pawn h2
Black
- King d8
- Queen e5
- Rook a8
- Rook h8
- Bishop c8
- Bishop f8
- Knight b8
- Knight e4
- Pawn a7
- Pawn b7
- Pawn c6
- Pawn f7
- Pawn g7
- Pawn h7
Step 5 of 7
Why does it work?
When the knight moves away, your queen gives check. We call this discovered check. As with a pin, three pieces stand in a line; this time the middle piece is yours, and it may move.
Black must get out of check first. That lets the knight go almost anywhere, including a square where it attacks something valuable. Be careful next to the king: if the square is unprotected, the king can capture your knight.
If both pieces give check at the same time, it is called double check. Then only a king move helps.
Key idea
When giving discovered check, move the piece out of the way to the square where it wins the most.
When does this apply?
This applies if your opponent cannot get out of check cheaply. Check whether the king can capture your moving piece and whether your opponent can capture the piece giving check.
Step 6 of 7
New position, same idea
The board is turned round. This time, a rook opens a path for a bishop.
You are playing Black. Use discovered check to win as much as possible.
Arrow keys move the focus across the squares. Enter or Space selects a piece and moves it to a highlighted square. Escape cancels the selection.
Choose a move from a list
Position as a list
White
- King h1
- Queen d1
- Rook f1
- Bishop c1
- Pawn a2
- Pawn b2
- Pawn c2
- Pawn f2
- Pawn g3
- Pawn h2
Black
- King g8
- Queen c7
- Rook d5
- Bishop b7
- Pawn a7
- Pawn b6
- Pawn e6
- Pawn f7
- Pawn g7
- Pawn h7
Step 7 of 7
Nimzowitsch and today
Source
Nimzowitsch calls discovered check a pin in which the piece in between has changed sides. Again, three pieces are involved: the one threatening check, the one moving away and the king behind it. He says the moving piece may go anywhere: it may capture whatever it can reach because the opponent cannot recapture, attack a valuable piece even from a square the opponent controls, or choose a better square. Against double check, he says, only the king’s escape helps. The texts are newly written for the course; the double-check exercise comes from a game Nimzowitsch presents.
- My System, chapter 8 (in German): “Das Abzugsschach” (original text not yet published)
- My System, 8.1 (in German): “Der Verwandtschaftsgrad zwischen Fesselung und Abzugsschach” (original text not yet published)
- My System, 8.3 (in German): “Das Doppelschach” (original text not yet published)
Today’s view (editorial note)
Today we also speak of a discovered attack when the uncovered piece attacks something other than the king, for example the queen. The position in the first three exercises is a well-known trap in the Petroff Defence: 1.e4 e5 2.Nf3 Nf6 3.Nxe5 Nxe4 4.Qe2 Nf6 5.Nc6+. After 4.Qe2, only 4…Qe7 holds.