When The Spawn retreated at the end of The Havonian - Spawn War, it was not out of fear, it was to get reinforcements. Before The Harbingers exited Havona to go into hiding, they built Havens. To protect all other sentient life from The Coming Storm, or The Spawn's Return. The Storm also goes by many other names, such as Armageddon, or Doomsday. When The Spawn return, they will supposedly have enough numbers to destroy all of Havona. The Spawn are Galaxy Eaters, a hellish parasite that can spread over an area the size of the U.S. in less than 24 hours, over an area the size of Earth in less than a week, and an area the size of our Solar System in less than a Year. Over the course of less than 10 Years one single Spawn infestation can destroy our entire Milky Way Galaxy.