Arguably this is his only motif.
Elden ring is basically a huge ungodly mountain of character flaws.
[0] is the Asylum Demon, which is literally the first boss in Dark Souls.
Bloodborne cranks the gross-out factor up to 11 with [1] and [2].
[0] https://i.ytimg.com/vi/6qCB_x7KQR8/maxresdefault.jpg
[1] https://bloodborne.wiki.fextralife.com/file/Bloodborne/ludwi...
[2] https://1.bp.blogspot.com/-kXCskueejFY/XLlAKLB-nmI/AAAAAAAAd...
Ludwig (your second example) is, I think, a perfect example of this. He's one of the most disgusting designs they've ever made, and yet when he stands during his second phase, and the music swells, you get an immense feeling of the grandeur and power of Ludwig before his fall to the disgusting creature he became:
https://youtu.be/7n1qe2ZSTPA?t=102
That being said, I think FromSoft's designs sometimes ARE "just gross". But it's an admirable guiding principle, even if they don't always hit it.
[0] https://vignette.wikia.nocookie.net/dragons/images/a/ac/OtTP...
[1] https://static.wikia.nocookie.net/darksouls/images/4/49/Ceas...
if you want to see pure grossness like they try to avoid watch something like peter jackson's "dead alive" the souls really nail a kind of tragic or even self respecting aspect of deformation in their more "offputting" characters.
If you explore a bit you'll find a site of grace that's directly in front of one of the gates. I also switched to frost damage and it made the fight almost trivial.
Also if you never lock on to either of them, they are less aggressive.
I love that these games are turning to my old man. “Back in my day you Had to think your way through the problems…”
>I remember when I was drawing the Undead Dragon, I submitted a design draft that depicted a dragon swarming with maggots and other gross things. Miyazaki handed it back to me saying "This isn't dignified. Don't rely on the gross factor to portray an undead dragon. Can't you instead try to convey the deep sorrow of a magnificent beast doomed to a slow and possibly endless descent into ruin?"