so i'm curious as to what the "cost" of shadows locations are, as far as QoD Viserion is concerned. for example, does the black cells cost 1, since it is s1, or is it 3?

From the Shadow's Rule Sheet:

"If the value of a SHADOW card’s 'printed cost' must be determined (because of another card effect), the value is determined by adding the cost of playing the card into Shadows (two gold) to the cost of bringing the card out of Shadows (as shown on the card)."

thanks ktom!