2022-10-07 : A card has the same art as another card if it has the same illustration by the same artist. If a card is modified with an art sticker, its art is no longer the same art as its original card. But other stickers that happen to be placed over the art do not modify the art. Modifications to the art that have been made outside of game effects (for example, signatures, your doodles, the occasional haiku) do not modify art.

2022-10-07 : Ignores things like frame differences and printing variations when determining whether a land card has the same art as other cards. For example, a land card and the extended-art version of that same land card have the same art, even though the latter shows more of the art.