Hylonomus
A ballpine hammer to the cranium will take out that dog.
There is a great move for dogs too... you let it clamp down on your arm, then you reach your other arm around the back of its neck, then push foreward with the arm its biting on. If done properly it should crack the ******** neck.
I got attacked by a dog once, it jumped up and went to bite my arm. I pushed my arm as far in its mouth as it would go then kicked the ******** repeatedly in the nuts. It didn't hold on for long