If you get some gold pine resin (available in one of the houses in the undead burg*), the falling attack does a ton of damage, just went through that area, used the method FLD described combined with the lightning effect of the gold pine resin and it took almost half of his health (using a club without any upgrades), after that I just had to use 3 black firebombs (you get 5 in the house below the dudes that are throwing firebombs at you, the path you take from the undead burg bonfire) to kill him.