After a long and desperate struggle, our hero stands triumphant. The evil tyrant has been cast down from his throne and our heros swordpoint is at his throat. As our hero gets ready to make that fateful swing, the villain tells him, "No, you cant 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!.
Compare Can't Kill You, Still Need You, a role reversal where a villainous character realizes that they actually do require the continued existence of their victim (for whatever reason), and refrains from killing them as a result.
- Dragon Ball Z: Babidi tries this line when Piccolo attacks him, saying that he's the only person alive with any kind of control over Majin Buu, and if he's not around then Buu will run wild and destroy everything he sees. Piccolo points out that Babidi was planning on using Buu to destroy everything on the planet anyway, so he doesn't see how that's an improvement.
- 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.)
- 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.
"Fools! In destroying me, you destroy yourselves!"
- Mistborn: The Lord Ruler. "You dont 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 hes shot, Arthur, the Overseer says "You know what that madman's doing to my city. To our city. You need me."
- Fallout: New Vegas: Mr. House.
- 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.
"Whos going to make the cake when Im gone? You!?"
- In Resident Evil 6 , Derek Simmons, the head of the Family tries this during his boss battle... fruitlessly.
Simmons: You... have no idea... what would happen if I DIE!!!
- 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.
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.