After he saw the reliefs within the city ruins, Hao Ren knew that the civilization on the planet had a massive self-preservation mission going on during their final moments. They had launched a massive spaceship to send the "embers" into space, and while the reliefs did not record what happened afterward, it at least presented a possibility: some of the denizens of the planet probably managed to escape.
Therefore, his suspicion was not without merit: the aircraft he saw during the day was probably not from the planet itself.
"I think Mr. Landlord's right," Lily, as the resident creative graduate puppy was the first to voice her support. "The surface of the planet is the First Born itself, and fighting the First Born on the surface is pretty much a lost cause. So rather than a land-based resistance army, I think it's more probable that they were the living descendants of those who went into space."
