Grass Wonder, the celebrated Japanese racehorse and beloved inspiration for an Umamusume: Pretty Derby character, has passed away at the age of 30. The announcement came from Big Red Farm in Hokkaido, where he enjoyed his twilight years in peaceful retirement. He succumbed to multiple organ failure linked to aging, after previously showing no signs of serious illness.

A Champion’s Career

Born in the United States in 1995 and raised in Japan, Grass Wonder burst onto the scene in 1997 with an unbeaten juvenile season. His highlights include record-breaking performances at the Asahi Hai, back-to-back victories in the prestigious Arima Kinen (1998 and 1999), and triumph at the Takarazuka Kinen. These accomplishments solidified his place among Japan’s greatest middle- to long-distance runners of the late 1990s.

Stallion Legacy and Cultural Impact

After retiring in 2000, Grass Wonder sired more than 700 winners, passing on his legacy through champions like Screen Hero and Maurice. In his retirement, he remained a fan favorite. Through crowd-funded donations of nearly 3,900 kilograms of hay, he even surpassed the famously beloved Haru Urara.

Beyond the races, he captured hearts as a soft-spoken, graceful “horse girl” in the popular game and anime Umamusume: Pretty Derby. His character’s popularity only deepened after the game went global in mid-2025. Developer Cygames also shared their condolences and honored his enduring influence. Fans mourned online, holding digital memorials and leaving tributes like “May you eat dandelions in heaven.”

A Final Note of Reflection

Grass Wonder enjoyed a long, fulfilling life and is remembered for his monumental impact on both racing and pop culture. His career, offspring, and enduring presence in the memories of fans ensure that his legacy will gallop on for generations.