Midori no Makibao

A white racehorse with a donkey-like appearance, Makibao faces challenges early in his racing career due to his looks and other disadvantages. Determined to succeed, he competes in major races using his determination and speed. His motivation includes overcoming a lifelong rival named Superhorse Cascade and reuniting with his mother, who was taken to settle debts at the farm. Despite numerous obstacles, Makibao progresses through various races, striving to become a top racehorse.