which concept do you think is the most effective strategy in sunzi’s art of the war

In my opinion, my favorite is the empty city plan . We stationed our troops in Yangping and sent them all to attack the Wei army, leaving only a few old, weak and broken soldiers in the city. Suddenly, I heard Sima Yi of Wei attacking the city with 150 thousand troops.
Zhuge undaunted in the face of danger, ordered to open the gates, also sent to the gate of the city. Zhuge Liang himself mounted the gate tower, sat on the piano, attitude calm, the sound is not disorderly. Sima Yi came to the city, saw this situation, heart became suspicious, afraid of an ambush in the city, so he did not dare to enter, ordered the retreat. I want to learn from Zhuge Liang's wisdom, not Sima Yi's excessive suspicion. I want not to panic, not to be busy, to analyze the situation carefully, to make the right decision, not to be confused by false appearances.