Complex sentence: Nathan and Ann go to the Bandakar Empire in order to bring Richard "back into prophecy" during which time they saved Richard and his companions from certain death, but were ultimately unable to aid him in restoring his gift to balance.
Split into simpler sentences: Nathan and Ann go to the Bandakar Empire in order to realign Richard with prophecy. They save Richard and his companions from certain death, but are ultimately unable to aid him in restoring his gift to balance.