I hate you, shit made me want to cry! 1000/10, gave me some really good ideas/story for games to make.
Further you play, it seems like his hitbox gets smaller due to attacks that showed it hit him yet didn't.
Bug (I think): with 2nd and 3rd attack of normal fight, when you do 3rd attack and immediately 2nd attack, there will be times where he doesn't jump and wont get damaged.