Shadrach, Mesach and Abegnego were the hot furnace version, according to Daniel. Nebuchadnezzar must have been impatient that day. Excruciating but short.

Impalement, yes, would be out in front with crucifiction as the nastiest possible. You might die faster with it, though. I imagine hitting a major blood vessel with the large pointy would be the merciful way to go...urgh.

Shall I revise that to stir up much anti-Semitism, then. Oh, Lord, protect your relatives from the bigotry and hatred of those who claim to follow You...