Roganda is queen of the unicorns of Unicorners.
Like all of her subjects, she appears as a white horse with a silver horn growing out of her forehead. In her case, the horn is accompanied by a silver crown, indicating her rank. Roganda can extend her horn to greater-than-normal length, and also make a trumpeting sound through it — abilities unique to her majesty. Her "neigh" is so loud and powerful that hearers tremble. All in all, she is a formidable creature.
The unicorns of Unicorners are largely ignorant of, and indifferent to, the rest of Oz; but Roganda is magnanimous enough to help Realbad rescue Ojo from the clutches of Mooj the magician. Afterward, she pays a visit to the Emerald City. (Ojo in Oz)