In 477, after Xiao Daocheng assassinated Emperor Ming's violent and arbitrary son and successor Emperor Houfei, the general Shen Youzhi, from his base of Jing Province (荊州, modern central and western Hubei), started a campaign against Xiao Daocheng. At that time, Xiao Ze, who had just previously been the chief of staff for Emperor Houfei's brother Liu Xie () the governor of Ying Province (郢州, modern eastern Hubei), was returning to Jiankang with Liu Xie. He had reached Xunyang (尋陽, in modern Jiujiang, Jiangxi) when news of Shen's uprising arrived. His associates all recommending speeding back to the capital Jiankang, but Xiao Ze instead took up defense position at Pencou (湓口, also in modern Jiujiang) to block the Yangtze River in anticipation of Shen's advancing east. When Xiao Daocheng received Xiao Ze's report, he gladly stated, "He is really my son!" (As it turned out, the defense was not needed, as Shen became mired in his siege of Yingcheng (郢城, in modern Wuhan, Hubei), and eventually his forces collapsed when he could not capture Yingcheng quickly, but Xiao Ze's tactical setup would have provided additional difficulty for Shen had he advanced further.) Xiao Ze was subsequently created the Marquess of Wenxi, and then the Duke of Wenxi, as his father progressed toward taking the throne. In 479, after Xiao Daocheng took the throne from Emperor Shun, ending Liu Song and establishing Southern Qi as its Emperor Gao, Xiao Ze was created the crown prince.