Rasputin

Grigori Rasputin was a Russian monk and mystic, remembered mostly for his enormous penis and the fact that he just would not die. He supposedly had some sort of healing powers, with which he healed the Tsar's son of hemophilia. He then developed a significant influence in the Russian empire's government through the Tsar's wife. Some other guys didn't like that, so they decided to kill him. First, they fed him cyanide via some wine and cake. Keep in mind, this cyanide was enough to kill five men. He just stood up and walked away from it. One of the men then panicked and shot him. He still wasn't dead. So then, the entire party takes clubs and whatever blunt weapons they could find and begin beating him with these. Once beaten into submission, Rasputin was thrown into a river. When his body was recovered, the cause of death was deemed to be drowning. Something that is not part of the story but is also fact is that, after Rasputin was buried, people exumed his body and tried to cremate him. His form appeared to sit up in the flames. However, there is a scientific explanation for this. Overall, he was a guy that was very well-endowed, historically the hardest man to kill, and there was some disco song that somebody wrote about him.