Complex sentence: After about another half an hour the final Muslim cavalry of 1000 warriors led by Khalid ibn Walid appeared from the west and attacked the Byzantine's left flank, now the Byzantines were totally encircled by the Muslim's cavalry.
Split into simpler sentences: After about another half an hour later the final Muslim cavalry of 1000 warriors led by Khalid ibn Walid appeared from the west and attacked the Byzantine's left flank. Now the Byzantines were totally encircled by the Muslim's cavalry.