Material Girl, meet the Mother of Dragons.
The 55-year-old singer shared a photo of the costume on Instagram, writing, "Happy Purim!!!!! All Hail All Queens! ##certainty."
Purim is a holiday traditionally observed with carnival-like celebrations and costumes. Madonna was raised Roman Catholic but converted to the Judaism-based Kabbalah in the 1990s.
We'll take this ensemble to mean Madge is a "Game of Thrones" fan. The show, meanwhile, returns for its fourth season April 6 on HBO.