Crucifixion.
torture; take a post , cross the person's hands above his head and cross his feet and nail them to the post. Do it in such a way that they have to straighten their legs to get air. but when the do the pain is excruciating. So they drop back down and can't breath. So up and down and up and down 'til they give up and suffocate. The reason the Roman soldiers broke the legs was to keep them from getting air.