Give material for a concrete advantage.
A sacrifice gives up material to gain something more useful: checkmate, more material, promotion or lasting activity. Calculate the opponent’s strongest replies. A sacrifice that wins in one continuation may fail against a different defense.
Bring your queen into the attack with check
Your queen gives check, so the opponent must answer it. In this continuation, your rook gives the final checkmate.
2 more clean runs (at any point) to reach Recall.