Man, 50 hours and you're at the final boss, crazy. I'm like 46 or something at Ornstein and Smough. Fuck those guys. Trying to kill Smough first because I want Ornstein's armour, but so much harder fuuuuuu.
Yeah that arch part was gay. I finally figured out that wearing a Havel and doing fat roll was getting me killed on that part so I just switched off to something lighter. Roll through arrows, yeeeeeah.
The invisibility bullshit is the fog ring you get from joining the forest covenant. Makes it so you can't lock-on. I don't know what weapon you're using but trying to hit those guys with a spear is super annoying. From is apparently taking a look at it and maybe nerfing it.