For truly violent lyrics, sung in a matter-of-fact way without a bunch of frat-boy affectation, it's hard to beat Lamkin. And doesn't that prove the point? After all, the Scots and Appalachian persons who sang those songs were really violent people, fond of settling their disputes with claymores, Bowie knives, or even better, guns!

How many Child Ballads can you think of where somebody gets burned alive? I can think of
Lamkin
Young Hunting
The Twa Sisters
Bonny Suzy Cleland

I'm no expert - there have to be dozens! Think what violence we perpetrate when we sing that stuff! We have a lot to answer for!