"Interstellar Cage" - Interstellar Epic
The "Nebula" civilization is not supreme. It is also a fugitive struggling in the face of "cosmic-level natural disasters". It sows civilization in order to screen out "partners" or "weapons" that can help it survive before disaster catches up. Earth's civilization was suddenly told: Either grow rapidly and jointly defend against enemies, or be abandoned as "bait" for delayed natural disasters.
