From Elite (1984) to modern titles like No Man's Sky (2016) and Starfield (2023), video games have been using Artificial Intelligence (AI) to generate alien planets and galaxies for decades. Blending science and science fiction, this AI generation allows anyone to explore new worlds, including AI agents that one day may navigate real alien planets. In this talk, Matthew Guzdial, an expert on AI in games, will cover how human developers use AI to bring these worlds to life.