Put some thoughts about the Blue Fairy into the character discussion threat about her: The Blue Fairy aka Mother Superior – https://oncepodcast.com/forums/viewtopic.php?f=35&t=710
In short for the discussion here: I think the powers of the Blue Fairy are much weaker in Storybrooke, still are, than they were in the Fairy Tale lands, because of the nature of her magic. So she wasn’t able to break the barrier spell Gold had cast before leaving for New York.
Guess it takes less power for the one who cast the barrier spell originally to kinda switch it off. So despite being weakened Gold was able to turn it off, so that not just he but his son, Emma, Snow, Charming could get into the shop. (not shown in the episode, but can’t show every detail)
Gold though was by then too weak to conjure another barrier spell for protecting the shop against the evil duo, so he needed Emma to do it.
With their combined powers Regina and Cora could overcome that spell. They didn’t try it on the first spell when Rumple was gone quite simply because they thought the dagger wouldn’t be in the shop anyway, waste of energy.
Alone it took Cora a little longer to overcome the second barrier in the shop, which Emma created after their fallback.
Makes all sense to me.
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