Shannon Hale said this quote

The first building she reached appeared to be an old barn. Only one young guard stood before its bolted door, staring at her with wide eyes, holding up his sword in defense, She heated his sword and he dropped it, his expression barely changing, as if he had been expecting that. She held up her two swords to his throat, but they were two heavy, so she dropped one and held the other with both hands. Where are the two Bayern boys kept? The soldier shook his head. BURN HIM, prompted the fire. The excitement of burning was simmering in her, heating her up for more action.