Fear
If the woman was from the Seven Realms, people could at least still think that they would be fine, they would at most only feel extremely threatened, but they should be safe as long as they did not provoke her.
However, if she was the Ancient Night King, the matter was really serious as the enmity between the two had practically reached the point where they wanted to annihilate each other.
The atmosphere instantly became tense because in the next second they might not all be alive anymore.
"Who can stop her?" People wondered.
"Does the Heaven Race have an ace up its sleeve against her?"
"Hmph, I don't think there's a chance even for them. Heaven Ancestor is powerful, but he can only deal with Old Geezer at most."