Ranga shoes maintain purity, but also demonstrate rank. There are two kinds of ranga: those used in the outer world and court ranga.
The ranga used outside Osrakum are believed to offer protection from the contaminating earth. When the Wise wear ranga on the outer shore of the Skymere, it is because this is considered more impure than the Isle.
Court ranga are more complex mechanical devices, indicating rank in proportion to their height—as is shown in the first diagram with the following key:
none – Ammonites and the Lesser Chosen.
1 Lesser Chosen Ruling Lords.
2 the Great, Sapients.
3 Great Ruling Lords, House of the Masks.
4 Empress, Grand Sapients, He-who-goes-before, Jade Lords.
5 the God Emperor.
the smaller figure indicates a barbarian of average height.
The second diagram shows the beginnings of an abandoned design project into the complex mechanics of the court ranga. I have an understanding of how they work, but decided it was better not to devote too much time to designing them in detail. Each different height of court ranga would require a specific mechanism.