GURPS Technomancer

From the introduction: On July 16, 1945, the Manhattan Project was completed. The first atomic bomb was detonated at the Trinity site in Alamogordo, New Mexico, and those words of power were spoken: “I am become Death, Destroyer of Worlds.” Combined with the explosion, which had torn a hole in spacetime, these words closed a necromantic ritual, bringing forth what is now known as the Hellstorm: a stationary tornado formed from the mushroom cloud of the explosion and shot with red lightning.