And then her eyes widened in surprise. As the lights of her Patronus came together, they no longer formed an otter. It was a massive panther, majestic-looking. It snarled at the Dementors, exposing its large fangs. Ears back, it looked almost evil. Its large paws were firmly planted on the ground in front of her. When had her Patronus changed? She didn’t even know that was possible. With a roar, the panther leaped towards the Dementors, pushing them away.