The one major victory that Wu has over Wei during this period comes in 228, when, with Sun Quan's approval, his general Zhou Fang pretends to surrender to Wei after pretending to have been punished repeatedly by Sun Quan.

This gambit deceives the Wei general Cao Xiu, who leads a large army south to support Zhou Fang.

According to legend, Cao Xiu did not believe Zhou Fang at first.

Zhou Fang cut off his famous locks of hair to prove his "loyalty".

In any case, Zhou Fang knew the territory, so he started to lead Cao Xiu into a clearing, where Cao could set up camp.

However, before they left, Cao Xiu had been advised not to trust Zhou Fang by one of his advisers, Jia Kui.

Cao Xiu had not heeded his words; however, and had not only bought Zhou Fang's ploy, but removed Jia Kui from the campaign and decided to march with seventy thousand troops.

On the way to the designated camping area, Cao Xiu is ambushed as planned.

Unable to gain the upper hand in battle, he thus retreats to make camp at Shiting (present-day Qianshan County, Anhui).

However, the camp is disturbed in the middle of night, and the soldiers run away in disarray.

Many sets of armor and carts of supplies are abandoned.

Cao Xiu sends in a memorial acknowledging his fault.

Many of his men are killed.

When he looks around for Zhou Fang, Zhou is nowhere to be found; he now realizes knew he had been duped.

Too ashamed to turn back, and believing that he has more troops and supplies than the enemy, he chooses to engage Lu Xun's army.

Lu Xun personally leads the central force and orders Zhu Huan and Quan Cong to take the left and right flanks.

The three armies advance simultaneously, and decisively take on Cao Xiu's ambushing troops.

Following that, the Wu troops pursue the fleeing Cao army until they reach Jiashi, where they annihilate some ten thousand men and win over ten thousand spoils of war; in addition, all of the Wei army's equipment and weaponry are looted.

Lu Xun regroups his men; and when he passes by Wuchang, Sun Quan instructs his attendants to shield Lu Xun with his own canopy when entering and leaving the palace doors.

Sun Quan bestows upon Lu Xun as reward precious items of the finest grade, honors received by no one else in this era.

Cao Xiu had barely escaped the battlefield with his life; he will die a few months later of an ulcer on his back, even after having been pardoned by the Emperor of Wei, Cao Rui.

Jia Kui, who had come along with Cao Xiu, had helped Cao retreat from the ambush.

For this, Jia Kui is highly praised by Cao Rui himself, and given many promotions.

He will live the last years of his life in happiness.

Sun Quan declares himself emperor in 229, an act that almost damages the alliance with Shu, as many Shu officials see this as a sign of betrayal of the Han Dynasty—to which Shu claims to be the legitimate successor.

However, Zhuge Liang opposes ending the alliance and in fact confirms it with a formal treaty later this year, in which the two states pledge to support each other and divide Wei equally if they can conquer it.

Later this year, he moves his capital from Wuchang (in present-day Ezhou, Hubei) to …

…Jianye, leaving his crown prince Sun Deng, assisted by Lu Xun, in charge of the western empire.

The first sign of the deterioration of Sun Quan's reign occurs in 230, when he sends his generals Wei Wen and Zhuge Zhi with a navy of ten thousand into the East China Sea to seek the legendary islands of Yizhou and Danzhou to seek to conquer them, despite the strenuous opposition of Lu Xun and Quan Cong.

The Wu navy is not able to locate Danzhou but locates Yizhou (Taiwan), and returns in 231 after capturing several thousand men—but only after eighty to ninety percent of the navy has died from illness.

Instead of seeing his own fault in this venture, Sun Quan simply executes Wei Wen and Zhuge Zhi.