李建成
By this point, Li Shimin was locked in an intense rivalry with Li Jiancheng, who was supported by Li Yuanji. Li Jiancheng and Li Yuanji, because they saw that Li Shimin had many fierce officers under him, wanted to try to tempt them to leave Li Shimin and follow Li Jiancheng. Li Jiancheng sent large sums of gold and silver to Yuchi to try to persuade him to join Li Jiancheng. Yuchi wrote back, declining the gift, and pointed out that he needed to be faithful to Li Shimin. Li Jiancheng, in anger, cut off his relations with Yuchi, and soon sent assassins against Yuchi. Yuchi took precautions, however, and the assassination was not successful. Li Yuanji then falsely accused Yuchi of crimes, and Emperor Gaozu arrested Yuchi and wanted to execute him; Yuchi was only saved after intercession by Li Shimin.