Bad ass motherf***ers from the science fiction world of Dune. Sometimes called the fremen death commandos. If you claim to have fought one you are a liar because you would be dead.
1) "And Gurney recalled the stories told of Muad'Dib, the Lisan al-Gaib -- how he had taken the skin of a Harkonnen officer to make his drumheads, how he was surrounded by death commandos, Fedaykin who leaped into battle with their death chants on their lips." -Dune
2) "Yo, I once saw a fedaykin and I started to bleed from the eyes" -random blind man