Encounter, befriend, or transform into over 100 strange and captivating alien life forms in this brand-new creature compendium for the Starfinder Roleplaying Game! Across countless worlds, orbiting distant stars, bizarre and wondrous creatures await discovery. Inside, you'll find rules and background information for a host of creatures—from undead androids and robot dragons to dangerous laser-spined plants and enigmatic sea skeletons. Many species come with detailed rules to create your own playable alien characters, including beings made of coral, animals uplifted by sentient fungus, and other truly unique creatures. Plus, this volume introduces a variety of new equipment and player options, including a set of augmentations that allow your character to adopt the extraordinary traits of dozens of playable alien species. Dive into the unknown and explore the truly extraordinary with Starfinder Alien Archive 4!