Star Conquerors, a.k.a. Starros are a race of starfish-like aliens that travel from planet to planet taking over the mind's of the native species.
Before the Star Conquerors were led by Starro the Conqueror, they were a race of nomadic space-borne aliens that acted in a similar way to bees and ants.
There are two different types of Starros: the Motherstar, which are massive in size, and the various small starfish offspring that obey the Motherstar's will. Starros travel from planet to planet by having a Motherstar land on a planet and send the various small starfish to attach onto the faces of every sapient being nearby. Since the small starfish drones are incapable of serving their Motherstar in their current state, they have to resort using a sapient being as a host to control the body and mind of said being to serve the Motherstar. Once the Motherstar lands on the planet's surface, every mind-controlled native inhabitant would protect and care for the Motherstar as it begins to give birth to various Motherstar eggs. Once the newly born Motherstars grows to their full size, they will then ascend into space in search other planets to convert and the Motherstar on the previous planet would remain there and take control of the rest of the planet.
It was until a Motherstar landed on the planet Hatorei where a native Hatoreian named Cobi who managed to fight against and disconnect himself from the Starros control and had the Motherstar hatchling latched onto his chest and gained control of the Starro race, to which he used them to conquer the Universe. Claiming the title "Starro the Conqueror".