The reason why Li Si chose this place as the launch site for attack planning was because they could use the high mobility of the transport plane to quickly deploy combat personnel within the Ancient States, and then launch a surprise raid on the Ancient States' base for the Creating God Project.
For the Otherworlders, especially the High-peak people, this was still a new subject. But for humans from Earth, it was already a mature, even an overused tactic.
Relying on traditional ground mobility, they could only get as close as possible to the target location and then transport and deploy their troops via manpower or animal power, which was both time-consuming and laborious, and the mobility was poor. With the help of the transport plane, they could directly break through the enemy's ground blockade, adopt leapfrog tactics deep into enemy lines, enabling them to launch attacks on the enemies' weak defense points with ease, and the mobility is also high.