Board Thread:General Discussion/@comment-28042201-20160323221129/@comment-24674051-20160329165808

Honestly, Ana is nowhere skilled enough to take on Emma. Ana would honestly be crushed by Regina, and we've seen Emma take Regina on more than one occasion. And, based on what has been seen so far, Emma's stint as the Dark One only appears to have deepened her magical talent in general (such as she did not know, or at least had not tried, teleportation prior to becoming the DO. Nor had she ripped out anyone's heart).

Also, Emma (as the DO) was able to stand toe to toe with Merlin.

Also, the comment about Emma not going for the kill... Lest we forget, Emma will kill if she has to. She killed Cruella, and that was before she became the DO. If it came down to kill or be killed, Ana gets blasted into the next universe.

About the only Magic Users (that we've seen) that could even think about standing against Emma are Rumple, Zelena, and Hades (and possibly Poseidon). And we may see a head to head match up against any of these in the future.