Umbara alphabet

The Umbara alphabet was a writing system used by the Umbarans, a species of pallid humanoids from the Ghost Nebula. It consisted of 26 letters, with a number of additional symbols for digits and punctuation marks. The basic shape of each letter or symbol was a circle or segment of circle, adorned with various dots, lines and other internal features.

Behind the scenes
"An entire Umbara alphabet was designed for use in these episodes."

- StarWars.com

Chris Glenn developed a complete Umbara alphabet for the Star Wars: The Clone Wars episode "Carnage of Krell".