In reality, even if there are guards stationed at the borders, it is impossible to completely seal them off. Because as long as the other side is determined and cunning, they will always find an opportunity. It is not just the Chu Dynasty that has spies in the Wu Dynasty; the Wu Dynasty also has spies lurking within the Chu Dynasty. Therefore, generally speaking, guarding the borders is meant to prevent a full-scale invasion by the enemy.
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Following the trail of their pursuit, the group of Purple Skeletons was nearly wiped out.
Chapter 138