Zelena (Once Upon a Time)
Zelena, also known as the Wicked Witch of the West and cursed as Kelly West in the seventh season, is a fictional character in ABC's television series "Once Upon a Time". She is portrayed by Rebecca Mader and was first introduced in the second half of the third season. After making recurring appearances in both the third and fourth seasons, Mader was promoted to series regular for the fifth and sixth seasons. She returned as a recurring guest star in the seventh season.
Ruby Slippers (Once Upon a Time)
The Oz events take place years after the flashback scenes from "Our Decay", they also take place immediately after Zelena is banished to Oz in "Swan Song" and before she goes back to Storybrooke in the present day scenes in "Our Decay". The Oz present events take place not long after Zelena leaves. The Underworld events take place after "Her Handsome Hero"