In the legends of the Dark Age, a Sky Castle was known as the city that would never fall. However, during the war at the end of the Dark Age, this myth of the Sky Castle being indestructible was debunked by the rebellion alliance led by Geresco. On the other hand, Lin Li really wanted it to be indestructible, so he did not neglect the defense system while creating a powerful weapon system during the transformation of the Sky Castle.
The original defense system of the Sky Castle was the canopy that enveloped the entire city, which allowed the Sky Castle to survive the constant bombardment of the terrifying Nether Storms during the thousands of years it spent in the Endless Void. Thus, it showed that the power of the canopy was considered very rare in this world.
However, Lin Li wasn't very satisfied with the defensive power of the canopy.
