so after some min-maxing tries i figured out that the Soul Shroud and the Vile Shroud Nodes in the Reaper Specialization Tree do not work properly.
Sould Shroud: Occording to the Tooltip you should get 4 armor per Point of int. In my current build i have 113 int, so i should get 452 armor. For some reason i get an exorbidant amount of armor to the Point i would call it broken.
Vile Shroud: It should give me the same amount of armor, for necrotic and Poison protection, but those node seem to not work at all.
If i spec out of Vile shroud i get the exact amount of armor that i should get (452).
So i guess the Vile Shroud Node just gives unintended high amount of armor instead of the described necrotic and Poison protection
For refference here are some screenshots (the % protections Count is different because i took the screenshots in different waves in Arena)
Thanks for the report. The specific bug is that Vile Shroud is not doing anything and Soul Shroud is giving more armour every time you enter Reaper Form.