From a cosmic perspective.
In the Wandering Star System, the three planets that orbit all seem to be Metal Planets.
The outermost Metal Planet Wandering needs no mention, being entirely metallic.
Both Green Star and Earth, after transformations, have a silvery appearance, looking like two metal planets as well.
On the surface of these two planets, layers of precise metal equipment are seen, resembling towering super suspension bridges, giving a layered sense of depth.
Under these circumstances, even sunlight finds it hard to penetrate, and to solve the surface living conditions, Earth Civilization and Light Synthesis Civilization installed refractive devices to allow sunlight to reach the surface smoothly through refraction.
Apart from the surface changes, upon becoming a Level 3 Civilization, the overall strength of the Wandering Alliance also saw a drastic increase.
