Xu Tui was making the most detailed tactical arrangements in the barbican in the defense fortress of the cosmic tunnel node of Asteroid 570.
The structure of the Spiritual Race's cosmic tunnel defense fortress was similar. There was a slender and solid passageway that was more than 500 meters long at the entrance. Then, there was a structure similar to that of a barbican city in Huaxia.
This slender tunnel greatly restricted the flow of attacks.
There were at most two enemies who could charge side by side in this tunnel at the same time. After the enemy rushed through the long tunnel, they would face the concentrated fire of the guards.
That was the function of a barbican.
There were hundreds of people who could gather on the top of the barbican in a semicircle. If the enemy rushed in, they could immediately focus fire. The construction concept of the Spiritual Race was actually completely correct.