The Black Unicorn Mount is a majestic and rare creature with a sleek, muscular build, standing tall with a height comparable to a large horse. Its coat is a deep, glossy black with subtle iridescent highlights that shimmer under sunlight, giving it an almost magical appearance. The unicorn's horn is spiraled and sharp, made of a dark, metallic material that contrasts with its coat, and its mane and tail are long, flowing, and silky, with a slight wave that catches the wind as it moves. The eyes are a piercing silver or gold, adding to its otherworldly presence. The mount's hooves are sturdy and slightly larger than average, with a faint glow when in motion, suggesting inherent magical properties.