Why does Regina, Zelena, and Rumple have to worry that witches are being killed? How does this effect them personally? Rumple seemed to think that the three of them would now be in danger?
Rumpel & company don’t know that the murders are limited to witches from that coven. As far as they know, all witches are at risk, or even all magic users. People who are already ensnared in a magical trap are going to be at least a bit paranoid about other magic-related dangers.
It’ll turn out to be just the coven, of course — and probably an internal job, Gothel gathering magic for herself the way she’s been shown doing — because there are only a few hours of storytelling left.
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