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So my sons and I are having a debate about Karn, the Great Creator's ability to use a "card from outside the game" and its format. The way I interpret the text is that in a casual, non-tournament game, I can choose any artifact outside the game from my collection and put it in my hand. Does that chosen card have to be within the format we are playing? In other words, if I'm playing standard, does my "chosen card" have to be within the standard format or can it be from any set? And if so, can it be one that's on the banned play list?