The Guardians discover Groot's home-world, Planet X, has been overrun by Symbiotes who will stop at nothing to get Groot's restarted World Pod for themselves to conquer the Galaxy. Then, as a comet covered in Symbiotes comes barrelling toward Spartax, the Guardians must team-up with Quill's sister Victoria to save the planet. And later when the Symbiotes escape to Asgard and Venomize Thor, Odin and other Asgardians, it's up to the Guardians to not only save them, but the World Tree (and the rest of existence) as well.