Shade in the Jeweled Amber games
In the cosmology of the realm of Amber Shades are the shadows of Amber that resemble Amber. Realms where Brand won, Bleys took the final step, killing Corwin and taking the throne, Fiona slew Oberon in personal combat, or any other variation.
There is a great deal of interaction between Amber and its Shades but as yet no Shade Realm is a member of the Golden Circle, despite being, cosmologically, closer to Amber then many of the GC kingdoms.
Among the Shades of Amber is one called Tosian-York