Plea of Personal Necessity

After a long and desperate struggle, our hero stands triumphant. The evil tyrant has been cast down from his throne and our hero’s swordpoint is at his throat. As our hero gets ready to make that fateful swing, the villain tells him, "No, you can’t do this. You need me!"

The nature of this plea can vary greatly. It may just refer to the hero(es) personally (such as villain being the only thing keeping their lair intact), or it may involve the world as a whole (when removing the villain will result in an Evil Power Vacuum, for example). The reality of the claim varies as well; it may just be a villainous ploy to throw the hero off his game. In any case, these pleas are rarely successful.

If the villain really is directly responsible in some sense for the well-being of the world, he is a Load-Bearing Boss. If, after he is cast down, worse forces arise, it may be a case of Better the Devil You Know, or the chaos of an Evil Power Vacuum. Whatever the reason, if he's telling the truth, killing him would be a clear case of Nice Job Breaking It, Hero.

Comic Books

 * In the second Superman versus Spider-Man crossover, Doctor Doom discovers that the reactor he invented as part of his master plan is about to explode, and tries to flee, only to be caught by Superman. He then shouts "Let me go! My genius must be preserved!!" (Superman didn't know about the incoming explosion at the time.)

Literature
""Fools! In destroying me, you destroy yourselves!""
 * The Elric Saga: Darnizhaan tells Elric and Dyvim Slorm that killing him will begin the death of the world they know. They decide to do so anyway.


 * Mistborn: . "You don’t know what I do for mankind." Surprisingly, he was largely telling the truth. On the other hand, he may not have been sane enough to keep doing what needed to be done.
 * The Manual of Detection: Shortly before he’s shot, says "You know what that madman's doing to my city. To our city. You need me."

Video Games
""Who’s going to make the cake when I’m gone? You!?""
 * Fallout: New Vegas:.
 * Half Life 2: Dr. Breen tries to convince Gordon that he, as humanity's go-between for the Combine, is the only hope for the survival of the species. No one else really seems to buy it, though.
 * In Portal, GLaDOS tries this. Being GLaDOS, she's not very good at it.

Western Animation
"Sideshow Bob: Because you need me, Springfield. Your guilty conscience may move you to vote Democratic, but deep down you long for a cold-hearted Republican to lower taxes, brutalize criminals, and rule you like a king. That's why I did this, to save you from yourselves. Now, if you'll excuse me, I have a city to run. Judge: Arrest the mayor. Bob: *is handcuffed* What!? ...oh yes, all those things I did."
 * In The Simpsons, after Bart and Lisa proved Sideshow Bob rigged the election to win his Engineered Public Rant ends with one of these. Essentially making this statement the source of his downfall.