Immortal unique monster bug

Hello.

I am experiencing an issue with unique monsters (and some normal mobs), becoming immortal/undamageable. I believe this issue is stemming from my Runegraft of Treachery that is applying my Discipline aura.

This issue shows up often when I am doing blight. The unique bosses will spawn, and I can damage their health and energy shield initially. However, at some random point, they stop taking damage to their health and energy shield. They only resume taking damage once their energy shield has recharged.


Thanks for any reply or insight that you can give!