Decoy

Decoy is a tactic where you force a piece to a square that it doesn't want to be on. This can be used to remove a defender, lure a piece into a fork or even lure a king into checkmate.

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White could play Queen to h7 but then the black king escapes to the f8 square, if only black king would be in h8 it would be checkmate.

So White lures the king into H8 by moving the rook to h8.

And now it is checkmate