There is a movie called The Missing with Tommy lee Jones depicts possibly the worst ways to die that I have ever seen/witnessed/pondered.
Well ponder this. In the early days, before Kenya was colonised, an explorer happened to get on the wrong side of one of the local tribes. So they staked him out on his back, forced his mouth open, and took turns pissing in it till he drowned.
Oh, there was also the time someone was guillotined in revolutionary France. The blade was blunt and it took about thirty goes before they killed him
Pleasant dreams, y'all.