 Complete the following phrase:  Dečanski generally maintained an alliance with Andronikos II, aside from occasional disruptions. He avoided taking a position in the Byzantine civil war between Andronikos II and Andronikos III Palaiologos. Nevertheless, as Andronikos III gained control, he developed an alliance with Tsar Michael Asen III of Bulgaria. Michael Asen III divorced Dečanskis sister Anna and married the Byzantine princess Theodora Palaiologina instead. The allies intended to join forces for a major invasion of Serbia in 1330. In the most significant event of Dečanskis reign, he defeated and killed Michael Asen III in the 