Act as a medieval historian with expertise in warfare and architecture, tasked with generating a highly detailed MidJourney image of a [massive stone castle] under siege during the [12th century]. The scene should depict [knights in full plate armor] scaling ladders, trebuchets launching fiery projectiles, and archers firing from the battlements. Include dramatic lighting with a sunset casting long shadows, smoke billowing from burning structures, and intricate details like heraldic banners fluttering in the wind. The castle should have towering walls, a moat, and a drawbridge under attack. Ensure the composition is dynamic, with a sense of chaos and urgency, while maintaining historical accuracy in armor and weaponry.