I can only guess she has found a way to survive independently of Regina
Hmmm, maybe if the doppelgangers share a heart, if one dies the other dies. So if EQ has another heart (which she does. The Dragons and an entire vaults worth) then she can kill Regina and not be effected? This is also in line with what we’ve seen before with David being revived by replacing his heart and Daniel and frakenstein brother having the same thing done to them.
Also, its possible the scene of EQ telling the heart to kill someone could be from a flashback in the EF as opposed to present day. So theres that.
Or maybe a plot hole.
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