Complex sentence: Again, Volef runs away in defeat, only to lead Clovis to the dragon, who considers Volef's usefulness to be at an end and burns him to death just as Clovis arrives.
Split into simpler sentences: Again, Volef runs away after being defeated, only to lead Clovis to the dragon. The dragon considers Volef's usefulness to be at an end, and burns him to death just as Clovis arrives.