We managed to find some news about the new wicked witch of Once Upon A Time and turns out it has to do with her Backstory!
Warning: If you do not want to know "Once Upon a Time" season 3 spoilers, then stop reading.
Viewers will find out the Wicked Witch's backstory on episode 16, titled "It's Not Easy Being Green." Co-creator Adam Horowitz said,
“She’s got a whole backstory and mythology. We used the original [L. Frank Baum] book as a jumping-off point, and then spun her in a hopefully unique, Once Upon a Time way.”
Unfortunately, fans will have to wait until the second to last episode in season 3 to discover the backstory and what her issue with the Evil Queen is. Some viewers are speculating that it may have to do with Robin Hood. It wouldn't be the first time that two women fought over a man, but of course this is just a theory.
It was recently revealed that Rose McGowan will be returning to play young Cora. This is a bit confusing because Cora died in season 2, but she is needed to tell the backstory of the Wicked Witch.
"Once Upon a Time" season 3 will return to ABC on March 9.