I had two ideas for the Chaos Die's Lord
The Unrelenting Void - Based on the traditional Greek belief of chaos being a void from whence all creation arose. This lord might take on an amorphous appearance; perhaps faceless. The Unrelenting void cannot be contained and their influence ripples throughout all existence. Dust that was once settled finds itself altered in the presence of this Lord. Nothing in the Cosmos is out of reach.
The Unheard - Sometimes the quietest voice in the room is the wisest. This lord is an elder whose face cannot be seen, perhaps cloaked, trying to tell you something important but the rest of the voices in the room (the other lords) are too loud. The Unheard tries to tell you how the half-truths and twisted messages of the other lords should be interpreted to reach the truth.