Kathleen’s central Dreaming is Arnkerrthe - the Thorny or Mountain Devil Lizard, a small lizard with sharp spikes on its head and back, which normally roams over a wide area. It moves in a quasi-circular fashion, leaving an exquisite pattern of tiny, not-quite-concentric tracks, with its travels through Kathleen’s country depicted regularly in her artworks. These have become something of a trademark in Petyarre's work in which she recreates the journeys of Arnkerrth through sandstorms, over sand dunes, across hills, through watercourses, and even underground.

The Mountain Devil Dreaming is connected to a large stretch of country called Atnangkere, where Kathleen was born and grew up. It is country that is constantly changing, as does the chameleon-like lizard, from place to place and over time. Kathleen began learning the Dreaming narrative of Arnkerrthe from her grandmother when she was a child growing up in the 1940s. Today, almost all of Kathleen Petyarre’s paintings are about the long journey made by her Dreaming ancestor throughout the expanse of land and her artworks for sale are the jagged delineation of her sandhill country around Atnangkere, often depicting an aerial perspective.