History: (My Greatest Adventure #82)-The Green-Headed League was founded by three extraterrestrials from an unnamed planet. They were sent to Earth to earn trusted positions among humankind, and bury a thermal machine underground. The thermal machine would one day cause a worldwide heatwave, at which point other aliens from their homeworld would arrive and "save" Earth. The League hoped to conquer Earth through this bloodless coup. The site where the thermal machine was buried became a government project, cutting off the League's access to it. A preposterous tabloid report accused the Chief of being an alien, so the League asked for his help in recovering the machine and fulfilling their conquest of Earth. The Chief played along, sending the Doom Patrol to recover the machine, but as soon as it was unearthed the League pulled a double-cross. The Doom Patrol destroyed the thermal machine and thoroughly whupped the Green-Headed League. The League now believed that the Chief came from a far superior race, so they left the planet Earth, never to return.