Ha! Take that, game! Finally done with 1-4. The boss was brutal! I don't really know how I feel about the whole soul drain thing. I found it really irritating to be forced to do grinding session between attempts because of that attack. Just before the try when I actually beat him, I had to grind to get back 16 levels that he had stolen from me. Not fun! But then again, because of me hating the soul drain, I really wanted to beat him and have it done with. This made the battle really tense on the attempts when I actually got somewhere.
There were two things that allowed me to beat him. First, of course, getting more familiar with his moves, learning when to attack without risking too much. But also switching to the dark silver armor set, which I found provided rather good defense. I guess most of his attacks are magic based? Also it allowed me the use of the fast roll, when I had the ring of great strength equipped. Something which could not be said for the brushwood set I used on earlier attempts.
Now I'm debating whether to beat 2-3 and then the game, or if I should try the black world tendency content out. Currently leaning toward the second alternative, but I am still undecided.