magical creature, thestral, breeding pen, dark horse-like body, leathery wings, skeletal features, glowing eyes, ethereal, multiple thestrals, nurturing behavior, protective stance, enchanted forest, mystical fog, moonlit night, dense trees, hidden clearing, magical barrier, ancient runes, soft ambient lighting, high detail, fantasy setting, 3/4 view, atmospheric perspective, detailed textures, organic structures, serene environment, magical ecosystem, otherworldly beauty, high fantasy concept.