Xxenos, a military working dog, rests during one of his combat deployments.The retired MWD passed away earlier this year at the age of 10. Xxenos had been retired three years and deployed three times during his career; twice to Iraq and once to Afghanistan. Xxenos was a Marine specialized search dog. - Xxenos, a military working dog, rests during one of his combat deployments.The retired MWD passed away earlier this year at the age of 10. Xxenos had been retired three years and deployed three times during his career; twice to Iraq and once to Afghanistan. Xxenos was a Marine specialized search dog.