Four sets mention snow as a card type (Ice Age, Alliances, Coldsnap, Future Sight). Three of the sets have snow permanents, two of them have non-lands with the type, and only one has more than one snow card.
Ice Age brought about the type in the form of Snow-Covered basic lands. The rules were thus: 1) It's a basic land, but it's snow covered. 2) Some other cards might refer to snow-covered lands. 3) That's it. There were a few cards that referred to these lands, but the bonuses to play snow lands were not that great, (see Karplusan Giant.) and the drawbacks were pretty bad (see Avalanche). Few people, if any, used the “snow” cards. Alliances only had a handful of cards that mentioned snow-covered lands, and those cards are quite forgettable (see Viscerid Drone). It wasn't until Coldsnap that snow was recognized as a valid mechanic. The set was supposed to be the “lost” third set in the Ice Age block and had TONS of snow-y things happening in it. The snow-covered basics returned along with a cycle of dual “comes-into-play-tapped” lands (or as we say now, “enters-the-battlefield-tapped”).
Wizards also made a new supertype for cards called Snow. All the snow covered basics had the type line: “basic snow land – whatever” and the new rule was that any mana drawn from a Snow permanent had the type “snow” as well. They threw the type around to all the colors, giving a whole lot of creatures the new supertype for what seemed like no reason at all. (A few of the creatures had activated abilites that used snow mana as a cost, such as Rimefeather Owl, but I have no idea why Adarkar Valkyrie and Gutless Ghoul are snow creatures.)
There were a few things from Coldsnap upon which I decided to improve. While Coldsnap used snow as a tacked-on word to colored permanents, the world I'm building has Snow as a central theme and colored snow permanents don't feel right. Why should something be snow if you can cast it without using snow mana? The lands in Coldsnap (such as Mouth of Ronom and Scrying Sheets) do feel right, and I decided to use that idea to build my world, the plane of Frostmere.
Frostmere is so named because of the harsh, icy conditions that have been part of the plane since its inception. Endless blizzards block off parts of the world which mortals have yet to reach. Magic here is made from necessity, created from the frozen lands in which its casters reside. The influence of the colors of mana is much less pronounced than the mana of the snow and ice surrounding everything. In this world, snow is colorless. There are a few colored spells that are Snow, but they are influenced by the cold; any spell or permanent that is designated as Snow will have some connection to it. Take a look at this:
This card is the base for the whole set. It is now possible to create a colorless snow deck, helped by the fact that a quarter of the set is snow-centric. I chose to use the symbol for Snow mana instead of just the colorless 1 because it is more evocative of the setting and feeling of the set. This land will be in the rotation with the other basics and snow-covered basics in packs.
You can use snow-covered forests in your colorless deck, but what's the point? You don't need them to cast this:
Tomorrow, I'll talk about the identity of Snow Instants and Snow Sorceries in Frostmere.