Such is the nature of all-out war waged by large empires: once it enters what is called "garbage time," it cannot be resolved in a short while.
Quicksand Empire's tolerance is very small, so the period of using cannon fodder didn't last very long. It persisted for only a few months. Quicksand Empire is called an empire because it has a sixth tier and covers a vast territory.
However, its location in the desert, which is unsuitable for the survival of other creatures, is exactly why no one has ever managed to annihilate Quicksand Empire. Their concern for Divine Spirits differs from that of Du You; many nations do not believe in the existence of Divine Spirits.
And during this "garbage time," Du You's movements were somewhat restricted. He often traveled between Earth and the Yalan World.
At some point, Du You discovered that the sisters were now able to enter other worlds without him.
