Ascendant Spirit

{S}{S}: Ascendant Spirit becomes a Spirit Warrior with base power and toughness 2/3.
{S}{S}{S}: If Ascendant Spirit is a Warrior, put a flying counter on it and it becomes a Spirit Warrior Angel with base power and toughness 4/4.
{S}{S}{S}{S}: If Ascendant Spirit is an Angel, put two +1/+1 counters on it and it gains "Whenever this creature deals combat damage to a player, draw a card."

Rimefeather Owl

Flying
Rimefeather Owl's power and toughness are each equal to the number of snow permanents on the battlefield.
{1}{S}: Put an ice counter on target permanent.
Permanents with ice counters on them are snow.

Boreal Druid

Into the North

Search your library for a snow land card, put it onto the battlefield tapped, then shuffle.

Scrying Sheets

{T}: Add {C}.
{1}{S}, {T}: Look at the top card of your library. If that card is snow, you may reveal it and put it into your hand. ({S} can be paid with one mana from a snow source.)

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Ohran Frostfang

Attacking creatures you control have deathtouch.
Whenever a creature you control deals combat damage to a player, draw a card.

Pull from Tomorrow

Dead of Winter

All nonsnow creatures get -X/-X until end of turn, where X is the number of snow permanents you control.

Mouth of Ronom

{T}: Add {C}.
{4}{S}, {T}, Sacrifice Mouth of Ronom: It deals 4 damage to target creature. ({S} can be paid with one mana from a snow source.)

Conifer Wurm

Trample
{3}{G}: Conifer Wurm gets +X/+X until end of turn, where X is the number of snow permanents you control.

Rimebound Dead

{S}: Regenerate Rimebound Dead. ({S} can be paid with one mana from a snow source.)

Ohran Viper

Whenever Ohran Viper deals combat damage to a creature, destroy that creature at end of combat.
Whenever Ohran Viper deals combat damage to a player, you may draw a card.

Frost Marsh

Frost Marsh enters the battlefield tapped.
{T}: Add {U} or {B}.

Rimewind Cryomancer

{1}, {T}: Counter target activated ability. Activate only if you control four or more snow permanents. (Mana abilities can't be targeted.)

Heidar, Rimewind Master

{2}, {T}: Return target permanent to its owner's hand. Activate only if you control four or more snow permanents.

Villainous Wealth

Target opponent exiles the top X cards of their library. You may cast any number of spells with mana value X or less from among them without paying their mana costs.

Thrasios, Triton Hero

{4}: Scry 1, then reveal the top card of your library. If it's a land card, put it onto the battlefield tapped. Otherwise, draw a card.
Partner (You can have two commanders if both have partner.)

Draugr Necromancer

If a nontoken creature an opponent controls would die, exile that card with an ice counter on it instead.
You may cast spells from among cards in exile your opponents own with ice counters on them, and you may spend mana from snow sources as though it were mana of any color to cast those spells.

Graven Lore

Scry X, where X is the amount of {S} spent to cast this spell, then draw three cards. ({S} is mana from a snow source.)

Dark Depths

Dark Depths enters the battlefield with ten ice counters on it.
{3}: Remove an ice counter from Dark Depths.
When Dark Depths has no ice counters on it, sacrifice it. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

Kaldring, the Rimestaff

{T}: You may play target snow permanent card from your graveyard this turn. If you do, it enters the battlefield tapped.

Jorn, God of Winter

Whenever Jorn attacks, untap each snow permanent you control.

Jorn, God of Winter // Kaldring, the Rimestaff

Ice-Fang Coatl

Flash
Flying
When Ice-Fang Coatl enters the battlefield, draw a card.
Ice-Fang Coatl has deathtouch as long as you control at least three other snow permanents.