Board Thread:General Discussion/@comment-26391241-20150511234157/@comment-15736398-20150512193651

I feel confident in saying that the only affect Emma's innate light may have on the Darkness is that it will have to work harder to corrupt her than it did either of the two previous Dark Ones we've seen.

The writers are not going to suddenly change the way the Curse of the Dark One/the Darkness works just because they've made Emma a victim of it, as doing so would completely negate the point of making her a victim of it in the first place.

As far as why the dagger was left behind when Emma vanished, I highly doubt it was a conscious decision on her part.

I also think it's more likely than not that, whereever she ended up, it's going to be somewhere where her appearance will match that of the two previous Dark Ones (i.e. scaly and glittery) AND somewhere where she can't feel/hear the pull of the dagger.