Reference article
Green Flat-Haired Duck’s Race
Green Flat-Haired Duck offers this race in City.
Entering
Click the local rival and select a duck. You need Jumping level 50.
Course
Running and jumping. Ordinary races play automatically; trained skills and sufficient energy determine whether the duck reaches the finish.
Winning
Winning gives you 250 coins the first time you finish first. Once defeated, this rival no longer offers the race.
Progression
This race is optional for the tournament invitation.
Rival
This race is offered by 
Green Flat-Haired Duck.
Original Flash note
Some races give different coin rewards in the original Flash game.