The boiúna can turn the power of its gaze on a ship within 120 feet, causing it to halt as if stuck fast on a sandbar or anchor. If the ship has a pilot or captain, they can attempt a DC 23 Wisdom saving throw to resist this effect. On a success, their ship is immune to this effect for 24 hours. If failed, the ship cannot move for 1 hour unless the boiúna releases it. Casting remove curse on the ship grants the pilot or captain a new saving throw with advantage to end the effect.