De's former subordinate Huyan Ping (呼延平), who escorted them to the Qiang tribes. During Later Yan During Murong Chui's reign During Murong Chui's reign, Murong De served as a chief official and general, and Murong Chui often listened to his advice. For the first several years of Later Yan's existence, he often carried out campaigns to secure areas that were being held by semi-independent warlords. In particular, around the new year 387, he, assisted by his nephew Murong Long, was successful in defeating the Jin vassal Wen Xiang (溫詳) and the Jin rebel Zhang Yuan (張願), taking the territory near the Yellow River. In or around 388, Murong De married Duan Jifei, the younger sister of Murong Chui's wife, Empress Duan Yuanfei. (His previous wife, if any, was probably executed by Fu Chang when he rebelled with Murong Chui.) In 389, Murong De, along with his nephew Murong Lin, waged a successful campaign against the Xianbei Helan (賀蘭) tribe, forcing the submission of its chief Helan Na (賀蘭訥). In 393, when Murong Chui considered conquering the rival claimant (to rightful succession to Former Yan) Murong Yong of Western Yan, most officials opposed the proposal, arguing that the troops were worn out. Murong De was one of the few who agreed with the proposal, reasoning that Murong Yong was causing confusing among the people as to who was the legitimate successor. Murong Chui agreed, and in 394 carried out campaigns that led to Western Yan's destruction. In 395, Murong De was one of the generals who served under the command of Murong Chui's crown prince Murong Bao in an action calculated to punish Northern Wei's prince Tuoba Gui's pillaging of Later Yan borders, but with Murong Bao's incompetence, even with Murong De and other capable generals on staff, the army was crushed by Northern Wei at the Battle of Canhe Slope, and most of the army was captured and then slaughtered by Northern Wei. After the defeat at Canhe Slope, Murong De suggested to Murong Chui that if he did not conquer Northern Wei, Northern Wei would pose a future threat, since Tuoba Gui now would take Murong Bao lightly. Murong Chui agreed, and in 396 carried out a major attack on Northern Wei again. The campaign was initially successful, but as the army passed through Canhe Slope, the army was so mournful that Murong Chui became embarrassed and angry, and