On the latest Dragonflight Beta build, a new Drakewatcher Manuscript, the item used to add customizations to Dragonriding mounts, has been added: Renewed Proto-Drake: Embodiment of the Storm-Eater.
This item grants your Renewed Proto-Drake mount an appearance similar to that of Raszageth, the Storm-Eater – One of the Primal Proto-Drakes that lead the Primalists, and the final boss of the Vault of the Incarnates, the first raid of Dragonflight.