Zhao Hai nodded and said, " &Quot; that's right, that's exactly what I meant. That's why I called you here. We have hundreds of thousands of soldiers here, and it's hard to guarantee that there won't be a few enemy spies among them. So, we can't let the enemy know about this. We can let the enemy know that we have a barrier array, and we can also let the enemy know that we have a lightning array. However, whether it's a barrier array or a lightning array, they're limited, and they're all controlled by people we trust. This matter is even more important than the lightning and barrier circles. If we can't keep it a secret and take down the four cities in the shortest time possible, we'll be in a lot of trouble when the enemy's reinforcements arrive."