The reward challenge on last week's "Survivor" featured huge hay piles, a huge net see-saw, buckets of water, and a large puzzle. Themed to earth, air, water, and fire, it was a massive, multi-stage obstacle course, the kind of challenge "Survivor" does best. One player, Missy, injured her ankle during the challenge, which came into play throughout the rest of the episode.

It was, all in all, a very successful challenge. In the behind-the-scenes preview of the challenge below, host and executive producer Jeff Probst calls it "one of the best challenges of the season."

The challenge was named "Austin's Elemental Obstacle Course" after its creator. But that person isn't one of the regular crew members on "Survivor" challenge producer John Kirhoffer's team. He isn't even an employee or contractor.

That's because he's 13.

Austin Russel's Make-a-Wish dream was to help Survivor create a challenge, and he visited the show's Nicaragua set with his family and did just that. "It's not like we did it to do him a favor; we're a show, he pitched a great challenge," Probst says in the video.

The "Survivor" challenge crew made his idea come to life, which on "Survivor" involves a lot of work. Challenges are carefully designed and then constructed on location, often using local materials and labor. Then they're tested by entry-level crew members known as the Dream Team, so the challenge can be adjusted, and so the crew can practice filming it. When the cast does the challenge, there's only one take, so it has to be right.

To see what that process is like, read about my experience behind-the-scenes of a challenge rehearsal.

"Survivor" often re-uses epic and memorable challenges, and Kirhoffer said the chances are "pretty darn good" that Austin's challenge will be re-used, saying Austin is "part of the team."