Just defeated Yaga-Shura in his camp, and it was definitely much more difficult to damage him than I remember. After winning, I took a look at his cre file and saw, due to ascension and/or scs, he had 99 physical damage Resistance. That alone isn't a big deal, but I also had your revised armor component installed. With the +15% Dr from shuruppak's plate he has equipped, he had well over complete immunity to physical damage. I still managed to defeat him, but wanted to report it.
EDIT: After thinking about this, there are a number of mods that can force Yaga-Shura to have complete physical damage immunity due to changes in armors. I have gone ahead and performed a pull request for Ascension and posted the finding within the Ascension mod compatibility section.