Board Thread:Spoilers!/@comment-27060727-20171014181959/@comment-25926288-20171015021445

I do love witches, but I seriously doubt Robin is the Witch of NEF as she was around for several years, while Robin is like a toddler currently (plus they can't coexist).

Perhaps it's a gnereational thing. So, down the bloodline the Witches (firstborn) grow more powerful and Zelena was stronger than Cora, so Robin is the "Eighth". After all, 7 is a lucky number, lucky clovers are green, Zelena loves green. Stretching these connections, here.

One thing I do know: Writers and Math don't agree, so I wouldn't bother trying to figure out who's who.