I've encountered this both in Adventure mode and most recently in Quest mode. The exact case which spurred this post was my opponent activating Gavony Township's [2GW: Put a +1/+1 Counter on each creature you control] ability, while their board state consisted of exactly these 4 cards: 1 Taiga, 1 Plateau, 1 Gavony Township, 1 Servant Of The Scale.
In other cases, I have had an opponent play a 2-mana creature on the first turn of the game - having played only one of these dual lands. I see this most often with AI decks playing Blood Scrivener on turn 1 for some reason.
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