In 592, Yang Xiu appeared to be briefly recalled to the capital Daxing to serve as the head of the legislative branch of government, the "Neishi Sheng" (內史省), when Emperor Wen put him and the official Yu Qingze (虞慶則) in charge of investigating claims that the deputy head of the executive branch, the "Shangshu Sheng" (尚書省), Su Wei, had been engaging in factionalism. Yang Xiu and Yu found Su to be guilty, and Emperor Wen stripped Su of his titles. (It appeared that briefly thereafter, Yang Xiu returned to Yi Province.) In 598, Yang Xiu submitted an accusation that the general Shi Wansui (史萬歲) had received bribes from the chief of the Nanning Tribe (南寧夷), Cuan Wan (爨翫), in 597, to permit Cuan, after surrendering to Shi after a revolt, not be taken to Daxing, allowing Cuan to rebel again in 598. Emperor Wen nearly executed Shi over the accusation, but eventually spared him and reduced him to commoner rank. Over the years, as Yang Xiu became more and more accustomed to ruling over the region and grew arrogant and wasteful beyond the appropriate levels for an imperial prince. After Yuan Yan died in 593, without anyone to check his behavior, he made an armillary sphere – an item that only an emperor would be permitted to have. He also seized many men of the Liao (獠) tribe and castrated them to serve as his eunuchs, and used vehicles and decorations only appropriate for an emperor. Emperor Wen often told Empress Dugu, "Yang Xiu will surely suffer a violent end. While I do not need to worry while I am alive, when his brother becomes emperor, he will surely revolt." In one of the campaigns against Cuan Wan's forces, Yang Xiu sent his jester Wan Zhiguang (萬智光) to serve as the assistant to the general Yang Wutong (楊武通). Emperor Wen, finding this out and believing this act to be inappropriate, began to divide the forces under Yang Xiu's command. In 600, Yang Xiu's oldest brother Yang Yong the Crown Prince, over false accusations made by Yang Guang and Yang Guang's ally Yang Su, was deposed, and Yang Guang replaced Yang Yong as crown prince.