Lesson
White to move. Main line: 1. Qxh7#
Qxh7 is safe because the bishop on c2 protects h7 along c2–d3–e4–f5–g6–h7. The black king therefore cannot capture the queen, even though she has landed immediately beside it.
The pawn on g7 blocks one escape and the queen controls h8 and g8. The less obvious detail is f8: the knight on e6 covers it. Remove that knight and the same queen sacrifice would only chase the king away.
Queen-and-bishop batteries appear often against a castled king, but the battery alone is not enough. Before sacrificing on h7 or h2, inventory the flight squares and identify which piece controls each one; the “extra” defender is frequently what turns check into mate.