Yang Liang
In 598, angry that Ying Province (營州, roughly modern Zhaoyang, Liaoning) had been attacked by Goguryeo, Emperor Wen send his son Yang Liang and the general Wang Shiji (王世積) to attack Goguryeo—a campaign that Gao tried to dissuade Emperor Wen from but Emperor Wen launched anyway, and in fact forced Gao to serve as Yang Liang's deputy. Due to Yang Liang's young age, Gao was actually in charge of the operation, which ended in failure due to inadequate food supplies due to drought, as well as a storm destroying a large part of the fleet commanded by the former Chen general Zhou Luohou (周羅睺). Yang Liang, disgruntled at how Gao gave him little actual authority on the campaign and frequently disobeyed him, complained to Empress Dugu that he was fortunate to not have been killed by Gao, and this angered Emperor Wen as well.