Chaos and the warp are not only not limited to our galaxy, but not limited to our universe. https://comicvine.gamespot.com/images/1300-2752349 Chaos operates across the multiverse. And Daemons play with planets and stars in the warp and Eye of Terror. Chaos is too powerful to exist in the materium. That is why Daemons have a hard time manifesting. Reality tries to enforce it rules on them when they manifest. That one guy who made the thread asking if Chaos was limited to the galaxy, the codex does say Chaos operates across the multiverse. Like my scan for Karanak.