Reference article
Blue Swoop Duck’s Race
Blue Swoop Duck offers this race in Swamp.
Entering
Click the local rival and select a duck. There is no level requirement to enter.
Course
Swimming. Ordinary races play automatically; trained skills and sufficient energy determine whether the duck reaches the finish.
Winning
Winning gives you 100 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 
Blue Swoop Duck.
Original Flash note
Some races give different coin rewards in the original Flash game.