French Defense Mate In 1 Puzzle (Rated 895): Mate in 1 — Queen Sacrifice
This middlegame puzzle is a classic example of king safety deciding the game immediately. White’s queen is already deep in the enemy camp, supported by active pieces and pressure around the black king. The key idea is to recognize when a mating net is complete: the king has limited escape squares, defenders are overloaded, and a direct check ends the game at once. In positions like this, material count matters far less than the vulnerability of the king.