It featured a course of fifty wooden ledges that were fixed to the sides of the waterfall that dived the city. Those ledges were called "branches". A trained prowlgrin would leap from branch to branch all the way from the top to the bottom of the waterfall, and the fastest one down won. In the first run, each prowlgrin competing in the race would jump the course one at a time, and in a second run, the two fastest would go head to head, choosing their own route, in a grand race-off.
Bets could be placed on the different prowlgrins and their riders. Usually a very well-known colonel in the Hive Militia was the favourite. The odds on Dominix and Rumblix were both forty to one, meaning that large sums of money could be won if an outsider finished first. A grossmother lost two thousand Hivers after she placed a bet on Thebius Spave and Verginix. To bet on a prowlgrin, you would buy a wooden wager stick with the prowlgrin's name carved into it.
- "Whisp" and her prowlgrin Dominix for Tillman Spoke - Started twentieth, finished first.
- Cade and Rumblix - Started twenty-first, finished second.
- Thebius Spave and Verginix - Started first, previous champion.
- Rove Dugget and Felvix - Started second.