Badlands

The Badlands are a region in North Aerona on Dominaria, east of a jagged sierra and north-west of some plateaus.

The Badlands are almost two different lands: tall spires, ridges, mesas, all riven in a thousand places by ravines, gulleys, and arroyos, some a mile wide, some too narrow for a horse. The upper reaches are sixty or seventy feet high. Some tops are only big enough for an eagle's nest, others are razor-sharp knifebacks.

They were the kingdom of the wizard Haakon the First, self-proclaimed King of the Badlands until he was defeated and his fortress destroyed by Gull and Greensleeves' army.

Speculation
The Badlands are likely the unnamed region between Hammerheim and the plains of Muronia and Wrenna on the map of Aerona.