◇ Just read — no move neededThe horse that governs
挂角马 — the corner horse — stands on the palace corner (d8 or f8). From there it never checks a centred king directly; instead it governs: the f8 horse stares at d9, the escape square on the far side of the palace. Pair it with a chariot and the geometry closes: the chariot attacks through the open gate, the corner horse covers the gate's twin, and a lowly pawn seals the middle door. Three pieces, each doing one quiet job.