Clathrates Nanotechnology Rogue Microbes Space War Stellar Explosion Unknown knowns Supervolcano Cyber attack Paranormal Solar flare Nuclear winter Bio weapons Supernova Known unknowns Electromagnetic pulse Extraterrestrial Climate change Antimicrobial resistance Genetic modification Neobiota Pandemics Capitalism Ecosystem collapse Asteroid Coronavirus Geoengineering Hypersonics Nationalism Ozone depletion Super Tsunami Totalitarianism Unknown unknowns Superintelligence