I was just trying to complete LS2 with my 5th character and found that I cannot damage the shadow dragon at all. No matter what attack I tried with whatever weapon. I have checked my combat log after each attempt and the only attack of mine which was listed was “Wave of Wrath” which was absorbed!
The health bar of the shadow dragon did not move at all at any time during any attack with any weapon.
I am assuming that as I have killed the shadow dragon multiple times before (including with this character when helping guildies get the achievements) that this is a bug.
As killing the Shadow Dragon is important for completing this story step could someone please look into this?