San Pedro, California's battleship USS Iowa hosts the sixth and final qualifying round in a special all-military episode. The obstacles are the Quintuple Steps, Jump Hang, Log Runner, Monkey Pegs, I-Beam Cross, and Warped Wall. Ninja veterans include former Army vet Ryan Stratis, Navy officer Dustin McKinney, and Coast Guard rescue swimmer Robin Pietschmann, while former Marine Jeremy Prather and 72-year-old Chuck Mammay take on the course for the first time. (thetvdb.com)