This boss is clearly bugged. His impales have a 360 degree hitbox that should not be possible (I know this for a fact because I was behind him, and still got hit by the impale, my character was "teleported" to his front and got impaled also many times when I dodged to the side clearly before the attack landed, as my character got teleported to where they were to his front in similar fashion). There is no combo variation. When he is not impaling, he is thrusting away his sword then runs to the far end of the room where he can still got you again with his thrust. Rinse repeat. There is also no parry against him. One of the most bugged and uninspired bosses of the soul series. Just another big dude with a sword again as usual for DS2, only this one is also bugged. I'm glad Miyazaki San got management again in DS3 and fixed this ramshackle mess of a game as it were.