O. Hancock 
Penis
Also, she's only immortal in the sense that a lobster is immortal right? i.e. An explosion or a bottle of cyanide can still kill her, she just can't get a heart attack or cancer, etc. Cause otherwise what was the point of having epic battles with dangerous villains? If you can't die, wouldn't you just calmly whittle away your opponent's strength and then imprison them for questioning once they're too tired to fight anymore?