I am guessing its the sword. Given the title of one of the future episodes is ill boding patterns, which seems to a reference to a sword called Hrunting in Beowulf. And I quote: “rare and ancient sword named Hrunting. The iron blade with its ill-boding patterns had been tempered in blood. It had never failed the hand of anyone who hefted it in battle.” So I am guessing that sword probably has the power to kill EQ without killing Regina. They wouldn’t be putting focus on it if it weren’t special.
If that’s the case though and Rumple had it all along … why didn’t he use it to kill Zelena :s
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