I am attempting to write my first "sci-fi" piece of fiction and everything is going well except for one thing: why does "mad scientist" want to destroy the world and why is he mad? The story's protagonist is a high schooler who has the power to destruct the world when he turns 18 in 100 days. He isn't the only one of his kind. There are several like him on each continent to aid in the slaughter when it happens. That's all fine and dandy, but why should they destroy the world/every human? Every idea I have ends up sounding childish and Cartoon Network Villain-y. Up until now, my work had always been about sickness and tragedy. Rarely, I'd even pop out a romance. Never anything that required a physical antagonist. Any thoughts?