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"Now it is written that only a prince of Amber may walk among shadows, though of course he may lead or direct as many as he chooses on such courses. We led our troops and saw them die, but of Shadow I have this to say; there is Shadow and there is Substance, and this is the root of all things. Of Substance, there is only Amber, the real city, upon the real Earth, which contains everything. Of Shadow, there is an infinitude of things; Every possibility exists in somewhere as a Shadow of the real. Amber, by its very existence, has cast such in all directions. And what may on say of it beyond? Shadow extends from Amber to Chaos, and all things are possible within it. There are only three ways of traversing it, and each of them is difficult
If one is a prince or a princess of the blood, then one may walk, crossing through Shadows, forcing one's environment to change until it is finally in precisely the shape one desires it, and there stop. That Shadow world is then its one's own, save for family intrusions, to do with as one would. In such place I dwelled for centuries.
The second means is the cards, cast by Dworkin, master of the Line, who had created them in our image, to facilitate communications between members of the royal family. He was the ancient artist to whom space and perspective meant nothing. He made up the family Trumps, which permitted the willer to touch his brethren wherever they might be. I had a feeling that these had not be used in full accord with their authors intentions.
The third was the Pattern, also drawn by Dworkin, which could only be walked by a member of our family. It initiated the walker into the system of the cards, as it were, and at its ending gave its walker the power to stride across Shadows.
The cards and the Pattern made for instant transport from Substance through Shadow. The other way, walking, was harder."
~Corwin on Shadow
from Nine Princes in Amber
by Roger Zelazny
If one is a prince or a princess of the blood, then one may walk, crossing through Shadows, forcing one's environment to change until it is finally in precisely the shape one desires it, and there stop. That Shadow world is then its one's own, save for family intrusions, to do with as one would. In such place I dwelled for centuries.
The second means is the cards, cast by Dworkin, master of the Line, who had created them in our image, to facilitate communications between members of the royal family. He was the ancient artist to whom space and perspective meant nothing. He made up the family Trumps, which permitted the willer to touch his brethren wherever they might be. I had a feeling that these had not be used in full accord with their authors intentions.
The third was the Pattern, also drawn by Dworkin, which could only be walked by a member of our family. It initiated the walker into the system of the cards, as it were, and at its ending gave its walker the power to stride across Shadows.
The cards and the Pattern made for instant transport from Substance through Shadow. The other way, walking, was harder."
~Corwin on Shadow
from Nine Princes in Amber
by Roger Zelazny