Horrific Visions have a scaling progression system that can be acquiring and activated called Faceless Masks. Each Faceless Mask that is used will increase the health and damage done of all creatures in the Horrific Vision, in addition to a unique negative effect, but also increase the number of Corrupted Mementos that you'll receive!
Faceless Mask Details
All 5 Faceless Masks share this same effect. If multiple masks are active, their effects are added.
+25% Health of all enemies
+25% Damage of all enemies
+20% Corrupted Mementos gained
Faceless Mask of the Long Night - Reduces Maximum Sanity by 50%.
https://www.wowhead.com/guides/horrific-visions-faceless-masks-acquisition-rewards-mask-runs
Anyone have the Illuminati game cards to see what the fuck this faceless card means?