Complex sentence: The wolf-man, now free, pursues and kills Sam, and almost kills Darren as well; however, as Darren is being attacked, Mr Crepsley knocks the Wolfman unconscious.
Split into simpler sentences: The wolf-man, now free, pursues and kills Sam, and almost kills Darren as well. However as Darren is being attacked, Mr Crepsley knocks the Wolfman unconscious.