Board Thread:Spoilers!/@comment-25361971-20150128004028/@comment-25926288-20150305231631

The key parts that unravel most people's theories are :

-Robin would have recognized a change in his ex-wife. -Zelena herself said she isn't one for subtlety. -Magic glamour out of Storybrooke. (Magic can exist in items, so maybe) -Rumple or anyone not sensing a disturbance in the force of magic(Zelena). -Zelena's plan, What is she going to do, live with Robin forever and die in obscurity? -Zelena would waste her time and risk, not traveling back with Emma and Hook to charade as Marian (because Marian was unconscious and would have been stuck in Rumple's vault if not taken)

I rather smoke!Zelena possess Marian and slowly turn into Zelena than randomness. We'll see how it plays out! We're probably missing some details....