Nathan has been in the business of bounty hunting for almost a half a century, prompting many to refer to him as the "Living Legend." In fact, Reno once referred to Nathan as "Mount Rushmore" do to the respect he had earned in the field.

As an example of his success, he attended the Bounty Hunter Convention each year for 20 years, making a money back guarantee that he would seek out and catch on of the most wanted bounties by the end of the weekend. Going into his 20th year, his record was 19-0. At the 20th Anniversary Convention he pledged to bring in Reno raines, fully aware Reno was innocent of all crimes. Nathan did manage to track down Reno and take him into custody, but he let him go at the request of Bobby Sixkiller, and the fact he knew Reno was an innocent man.

Though the field of bounty hunting may of changed over the years, due to technical advancments, Nathan stays true to his original methods. While bounty hunterssuch as Sixkiller, use tracking devices and semi automatic weapons, "Duke" prefers his own unique sense of direction, and his fathers antique sixshooters.