Great read! Definitely some fun and frustrating bosses on this list from some really really great games.
Another great addition would be Orphan of Kos from Bloodborne. With it changing it's moveset 2 or 3 times thoughout the battle it made it difficult to predict, especially fighting him blind. Took me 2 dozen attempts or so to finally take him down! :P
Thanks for reading! That does sound like a great fight! I don't have a PS4, so I haven't had a chance to check Bloodborne out yet. Maybe this year!
If you get a chance I would definitely recommend it! I'm a big fan of Dark Souls 3 as well and it's a toss up which I liked more. :)