Snow-Covered Plains

The basic land that isn't quite basic: it produces white exactly as an ordinary Plains does, but it carries the snow supertype, and that single word is the entire reason it exists. Snow is a deck-construction tax disguised as a free upgrade. Any card that asks for snow mana or counts snow permanents (Skred, Marit Lage's Slumber, Dead of Winter, Coldsteel Heart) only works if you are willing to swap your ordinary lands for these, and the swap is paid up front in the manabase rather than on the payoff. The design discipline here is that the snow synergies live entirely on other cards; the land itself does nothing extra, which is what keeps it a clean enabler rather than a power creep on the basic land cycle. You take the supertype because something else in the deck rewards it, and in exchange you accept that the land is now a tracked, type-checked object: an effect that cares whether a permanent is snow can see this one where it could not see a generic Plains. As a basic land it still dodges the entire suite of nonbasic land hate, so the tax is purely a matter of building around the type, not of exposing yourself to new answers. Wizards has reprinted the snow basics across multiple sets to seed each new wave of snow-matters cards, which is the tell that the type was always meant as a recurring design lever rather than a one-off Ice Age curiosity.