Drawing an enemy piece—most frequently the King or Queen—onto a specific, highly dangerous square using a forcing sacrifice, setting it up for a subsequent tactical strike (like a fork or a pin).
Why it matters
A decoy is a sacrifice that puts an enemy piece — usually the king — onto exactly the square you need it on, so a fork or a check works that did not work before.
It is the opposite of deflection: you are not moving a defender away, you are dragging a target in.
See it on a board
The rook is thrown at h8 for one reason: to put the king there. On h8 it stands a knight's move from f7, and from f7 the knight hits the king and the queen at once.
Checked: this line wins at least 4 pawns of material.
How to play it
- White plays Rh8+!.
- The Black King is forced to capture the rook (Kxh8), stepping directly onto the lethal h8 square.
- Now that the King is perfectly positioned, White plays Nf7+, forking the King and Queen.
At each level
The same idea, said the way it is taught at each age.
Knight · ages 4–6
Sometimes you want the enemy king on a particular square. Give away a piece on that square, and the king has to come and take it.
Bishop · ages 5–7
Find the square where your knight would fork king and queen. Then ask what you could sacrifice to put the king there.
Rook · ages 6–9
Decoy first, fork second: most knight forks in real games are set up by a sacrifice a move earlier.
What goes wrong
- Sacrificing before checking that the follow-up really works.
- Forgetting the piece may decline and simply move away instead.
Questions people ask
- Does a decoy have to be a sacrifice?
- Usually. The point is to make going to that square the opponent's best or only option, and a free piece is the most convincing argument there is.