นักดาบเดียวดายในสนามรบใต้พระจันทร์สีเลือด

Dark fantasy anime illustration of a lone swordsman standing on a desolate battlefield under a giant [blood-red] moon. The character features [long dark hair in a messy high ponytail], glowing red eyes, and tattered black traditional clothing, holding a [katana] angled downward. In the background, a [ruined Japanese castle] looms amid dark, swirling clouds. Three prominent tattered war banners with Japanese kanji are planted among shadowy debris. Ominous, cinematic lighting with a color palette dominated by [deep blacks and intense crimson reds].