be it from player knowledge (which whether or not they keep that separate from character knowledge can still create some fun spooky realizations), or from character knowledge when someone Recalls Knowledge about the creatures. And some really on-the-ball players might note the presence of a vampiric mist and realize that might mean the influence of Nhimbaloth. This sort of encounter helps to set the flavor and feel and theme of the adventure path. Not every encounter in the dungeon leads to a step forward in the plot mechanically some lead steps forward in the plot thematically. Vampiric mists are thematically associated with Nhimbaloth, so it made sense to include one in the cupola, sort of like a moth being drawn to a flame.

Willfromamerica wrote: What exactly is the point of the battle against the Vampiric Mist in the cupola, other than just a cool fight? Defeating it doesn't even stop the haunt below from repeating, and there's no benefit to entering the cupola in the first place as far as I can tell.

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