"Mash It Up" is the twelfth episode of the animated series, Descendants: Wicked World. It premiered on December 13, 2015.
Inside Jordan's magic lamp, all the girls are gathered together for tea and a plan meeting. Auradon Prep's annual Friday night's ball is coming up and they need to decide on a theme for the party. Audrey is the first to come up with a suggestion; she suggests a "Pretty, Pretty Princess" theme. However, Ally points out they did that theme years in a row. Evie suggests on a "Who's the Fairest Party", but Jane finds her idea mean, because it would be a competition where the winner will get everything and the loser will get nothing. Lonnie then suggests a "Kick-boxing Hip-Hop Party", and Jane suggests on a "Garden Pumpkin Party".
It soon starts to get magical, and each time the girls come up with an idea for the party their idea conjures up around them. The following ideas they come up with are a "Genie Party", a "Fighting Knights Party", a "Party in the Dark", a "Magic Carpet Ride Party", a "Wonderful Wonderland Party", and a "Neon Glow Party". With all these ideas, they are unable to make a final decision on which one to use. So Freddie suggests using all of their ideas. Mal agrees it is a good idea, and pretty soon so does everyone else.
- Dove Cameron as Mal
- Sofia Carson as Evie
- Sarah Jeffery as Audrey
- Brenna D'Amico as Jane
- Dianne Doan as Lonnie
- Ursula Taherian as Jordan
- China Anne McClain as Freddie Facilier
- Jennifer Veal as Ally
- Mal, Evie, Audrey, and Freddie's genie outfits from "Genie Chic" make their second appearance in this episode.
- The Magic Carpet from Aladdin makes its fourth appearance in the series, followed by "Voodoo? You Do", "Lamp Sweet Lamp", and "Genie Chic".
- Ally makes her second appearance in this episode, followed by her debut in "Good is the New Bad".
- Jane uses her magic for the second time in this episode, and uses her mother's magic words, "Bibbidi-Bobbidi-Boo". In this episode she shows more control over it.