Custom Draft Lands?

I'm spectating a game in a draft right now (MM2) and the dude has some old basic lands. I thought XMage only adds the most current set's basic lands. How is this possible?
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I mean the logic is currently:varygoode wrote:I'm spectating a game in a draft right now (MM2) and the dude has some old basic lands. I thought XMage only adds the most current set's basic lands. How is this possible?