If we're talking about shit fights then can I nominate this one
Video where I eventually 'beat' it
Part I: https://youtu.be/6jZjmQQwJ-s
Part II: https://youtu.be/YAmC9phsZPM
I'm not excusing the camera here because it is BS, but if you go to the right there is a larger area where the camera isn't as bad - the part with the green titanite shard. It's odd for them to put loot in a boss room, so I assume it's there as some kind of visual signifier that that area is a better place to fight.