Lu Xun once said that human griefs are not truly connected, and I only feel that they are noisy (Lu Xun: I actually did say this).
While Ye Feng and his people were frantically building up their strength, the Mawu Alliance was doing the same. However, because Hogwarts had been blown up by Ye Feng, they could only scavenge for scraps.
As everyone knows, technology takes time to develop. Even if your theoretical foundation is mature, mass production still requires time, and quite possibly a significant amount of it.
Chapter 388