The Man Who Killed The World by Ray Cummings - Groff ruled the world through Fear. Fear of his awful power ... his twisted, mad brain. For one day that brain would crack. When it did, the World would dissolve in cataclysmic Chaos.

In his little tower, perched at the very peak of the great terraced pile of buildings which was his home and his citadel, Peter Groff sat brooding with hatred. The city, its factories, its vast plowed fields, lay stretched below him. Millions of humans, at play in little games. How he hated them! And they hated him—hated and feared him. It made him chuckle. For all his life he had worked and schemed and fought to make himself a power. The richest, most powerful man in the world—he had attained it. They had called him cruel, in his youth, with his ruthless business methods. He had laughed. Then they had no longer dared call him anything which would anger him. And he had laughed at that, while he had bought their governments and their armies with his money.

He was laughing now as he thought of it. In seventy years he had made the name Peter Groff a thing at which to tremble. Over all the earth, from the heads of his groveling puppet governments down to the lowliest child driving a plow in the fields, there was no one who did not secretly fear Groff, the power of his money, the sound of anger in his voice. Here in his citadel his servants trembled—and hated him. It was funny, because by their methods they had gotten nothing; and he had gotten everything.