10 Supervillains Who Thought They Were The Hero

The Watchmen graphic novel revolves around a detective called Rorschach tracking down the Mask Killer; a criminal who seems to be murdering costumed heroes. In the end, the killer is revealed to be the philanthropist, Adrian Veidt, who used to be known as the superhero, Ozymandias. After Veidt retired from vigilantism, he used his wealth to try and better the world. Over time, he convinced himself that mankind would end in nuclear war unless he did something drastic.

After he faked an alien invasion that killed millions, every war on Earth ended, forcing humanity to unite against a common foe.

Since the enemy didn't actually exist, it made every nation maintain a cease-fire. When the heroes see that Veidt's plan succeeded, they realise that they can't let society learn what he did as it would reverse everything he accomplished.

However, Rorschach wrote about Veidt's scheme in his diary before dropping it off to a newspaper office. In the story, Doomsday Clock, it is revealed that after the editor published Rorschach's notes about Veidt, every war on Earth reignited, undoing all of Veidt's hard work. Veidt's actions are vile but humanity would have lived in harmony if Rorschach kept the information to himself.