You.

There was something about you that ENRAGED him.

No matter what he did, he couldnt kill you. Which was infuriating.

You were a mere mortal, not anything he shouldnt be able to kill, and you've had so many close calls, so many times that you've should've died, but..you didn't.

Here he was, stalking you again. He didn't care about the other survivors anymore, he just needed you dead. There must be a way to get rid of you..