He said he was surprised, when crossing the finish line, that there was no one else around him.
Austin said he enjoyed the mud, the obstacles and the number of people.
His favourite part of the course was the ropes that went up an almost vertical hill.
Mokoia Intermediate student Kaia Hayes, 12, said it was her first time taking part, but wouldn't be her last.
She liked getting dirty and the climbing over the obstacles.
"It shows people what they can do."
(From left) Maegan Fraser, 13, Corey-James Davidson, 13, Anna Phillips, 12, and Megan Middleton, 13, all got muddy. Photo/Stephen Parker
Tomorrow is the first of the Rotorua Adult Tough Guy and Gal Challenge, with about 1200 adults registered to take part.
There is also a Corporate and Gym Challenge, with gyms, boot camps and companies taking on the event together.
Next Friday, is the secondary schools Tough Guy and Gal Challenge with more than 1000 students registered. These students can gain NCEA credits at this event.