 His final campaign, in 580, saw him siding with the regent Yang Jian against the general Yuchi Jiong in Northern Zhou's civil war, allowing Yang to defeat Yuchi and (after Wei's death) take over the throne as Sui Dynasty's Emperor Wen.More so than other prominent generals at the time, Wei was known for using atypical strategies in both offense and defense, including extensive use of espionage and forgeries to undermine the morale of opposing forces.Wei Xiaokuan was born in 509, during Western Wei's predecessor Northern Wei (which Western Wei and its rival Eastern Wei were divided from) -- specifically, during the reign of Emperor Xuanwu.