The Battle of Ruxu in the winter of AD 212 is a confrontation between Cao Cao’s attempt to conquer the south and Sun Quan’s defense of his territory. Sun Quan’s preparations turn Cao Cao’s expected advance into a series of costly surprises, while a dream of multiple suns gives the contest a prophetic dimension: Cao Cao comes to understand Sun Quan as a future emperor, yet pride keeps him from withdrawing at once. The campaign ends not with a decisive conquest but with Cao Cao’s retreat after a month of limited engagements and torrential rain.

Causes and preparations

The immediate crisis follows Lady Sun’s return to her brother’s capital. She reports what has happened, and Sun Quan sees an opportunity to attack Jingzhou. That plan is interrupted by news that Cao Cao is approaching with a force said to number four hundred thousand. Sun Quan orders a wall built at the mouth of the Ruxu as a first defensive line against the northern invasion. The sequence places the proposed move against Jingzhou beside the need to meet Cao Cao: Sun Quan’s attention shifts from an offensive opportunity to defending his own position.

Cao Cao sets out to conquer the south in the winter of AD 212 and arrives at Ruxu as Sun Quan’s preparations anticipate. Instead of an undefended approach, he finds the new wall and a large fleet anchored there, with Sun Quan seated confidently among the ships. The river mouth and its constructed defense shape the encounter before the armies meet: Cao Cao’s advance confronts an organized position rather than an open route south.

Surprise attacks and retreat

Sun Quan’s troops suddenly attack from the boats while others emerge from behind the wall and advance on Cao Cao’s position. Cao Cao and his men are taken by surprise. Sun Quan himself leads a cavalry charge up the hill, and Cao Cao is nearly killed; Xu Chu’s intervention saves him. Back at camp, Cao Cao rewards Xu Chu but rebukes the other commanders for their lack of courage. The reprimand does not restore the initiative. That night, Wu troops attack the camp and inflict heavy losses on Cao Cao’s army. Cao Cao escapes on horseback and rides away from the battlefield.

After finding shelter, Cao Cao spends time reading manuals of warfare. Cheng Yu confronts him with a strategic criticism: Cao Cao’s prolonged planning has allowed Sun Quan time to prepare his defenses. In Cheng Yu’s judgment, the circumstances now call for retreat, but Cao Cao refuses to accept that advice. The exchange makes the campaign’s central reversal explicit: Sun Quan has used the time Cao Cao allowed him to build a position from which his forces can surprise and endanger the invader.

The dream and the second clash

After Cheng Yu leaves, Cao Cao falls asleep with his head on the table. In his dream, he hears what seems to be the approach of innumerable horses and sees a bright sun rise from the river. Two more suns shine above it; then the river-sun rises and falls behind a hill at the edge of the camp. The sound of its fall wakes him. Cao Cao treats the vision as important enough to ride out with only fifty men to the place where he saw the sun descend.

There he encounters Sun Quan, wearing a shining helmet and silver armor. Sun Quan challenges Cao Cao’s right to pursue his lands despite having power and wealth in the capital. Cao Cao answers that Sun Quan has disobeyed the emperor and that he comes by imperial command. Sun Quan rejects this justification, arguing that Cao Cao has reduced the emperor to a puppet, and announces his intention to end Cao Cao’s tyranny. He charges, Cao Cao’s men engage, and war drums sound from behind the hill. More Wu troops pour out, and three thousand archers fire on Cao Cao’s force. Cao Cao flees again, with Xu Chu once more protecting him in his escape.

The dream’s imagery now informs Cao Cao’s interpretation of the battle. He understands the vision of the sun as foretelling that Sun Quan will become an emperor. Retreat to the northern state of Wei is the evident strategic conclusion, but Cao Cao’s pride prevents him from taking it immediately. The dream does not itself settle the campaign; instead, it gives the military encounter a political meaning that Cao Cao recognizes while continuing to resist its practical implication.

Standoff and outcome

For a month, the two armies remain opposed, making sorties without engaging in a decisive battle. At the start of the new year, torrential rain makes conditions miserable for the soldiers. Cao Cao finally orders his army to return to the capital, citing compassion for the men. The outcome is therefore a withdrawal rather than the conquest of the south: Sun Quan’s defenses and attacks have checked Cao Cao’s advance, while the weather and the prolonged stalemate help bring the campaign to a close.

The narrative links immediate military circumstances to the larger contest over authority. At Ruxu, Cao Cao invokes the emperor’s command, while Sun Quan counters that the emperor is effectively Cao Cao’s puppet. The dispute over who speaks for imperial power accompanies Sun Quan’s successful defense, and Cao Cao’s recognition of the dream’s portent connects the battle to the emergence of the rival rulers who would divide the Han empire. The novel presents the campaign as a struggle over territory and initiative, but also as an encounter in which political legitimacy and the future balance of power become visible.