Bold beyond belief
大胆穿心 (also 大刀剜心) is a sacrifice: the chariot throws itself onto the guarded heart of the palace — the very square the enemy king protects. It looks like suicide. Here it is mate: the cannon behind fires through Black's own centre pawn, so the recapture is poisoned, and Black's own camp plugs the remaining doors. Play the sacrifice — count the checks before you flinch.