an Entity references as follows:
"It's Not Easy Being Green" is the sixteenth episode of the third season of the American fantasy drama series Once Upon a Time, and the show's 60th episode overall, which aired on April 6, 2014. In this episode, with Rumplestiltskin as her slave, Zelena challenges Regina to a fight to the death and shocks the Evil Queen with the revelation of their familial connection, even while the town lays Neal to rest. Meanwhile, back in the past, in the land of Oz, a jealous Zelena asks the Wizard to send her to Enchanted Forest after discovering she has a sister, Regina, and that Rumplestiltskin is training her to become a powerful force to be reckoned with.