Final answer:
The 'Bronco Buster' sculpture by Frederic Remington matches the description of a bronze sculpture of a realistic, powerful stallion being broken in by a cowboy.
Step-by-step explanation:
The sculpture that is made of cast bronze, has the forms of a real horse, includes realistic details, and depicts a powerful stallion is the Bronco Buster by Frederic Remington. This sculpture is his first and most famous work, showcasing a cowboy breaking in a wild horse. Remington's sculptures, known for their textural detail and dynamic composition, often cast in bronze using the lost-wax casting method, have become iconic representations of the American West.