Rampant Growth

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

Iceberg Cancrix

Whenever another snow permanent you control enters, you may have target player mill two cards.

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.

Marit Lage's Slumber

Whenever Marit Lage's Slumber or another snow permanent you control enters, scry 1.
At the beginning of your upkeep, if you control ten or more snow permanents, sacrifice Marit Lage's Slumber. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

Ice Tunnel

({T}: Add {U} or {B}.)
This land enters tapped.

Hailstorm Valkyrie

Flying, trample
{S}{S}: This creature gets +2/+2 until end of turn. ({S} can be paid with one mana from a snow source.)

Narfi, Betrayer King

Other snow and Zombie creatures you control get +1/+1.
{S}{S}{S}: Return this card from your graveyard to the battlefield tapped. ({S} can be paid with one mana from a snow source.)

Rime Tender

{T}: Untap another target snow permanent.

Avalanche Caller

{2}: Target snow land you control becomes a 4/4 Elemental creature with hexproof and haste until end of turn. It's still a land. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Shimmerdrift Vale

This land enters tapped.
As this land enters, choose a color.
{T}: Add one mana of the chosen color.

Rimewood Falls

({T}: Add {G} or {U}.)
This land enters tapped.

Boreal Outrider

Whenever you cast a creature spell, if {S} of any of that spell's colors was spent to cast it, that creature enters with an additional +1/+1 counter on it. ({S} is mana from a snow source.)

Arcum's Astrolabe

({S} can be paid with one mana from a snow source.)
When this artifact enters, draw a card.
{1}, {T}: Add one mana of any color.

Moritte of the Frost

Changeling (This card is every creature type.)
You may have Moritte enter as a copy of a permanent you control, except it's legendary and snow in addition to its other types and, if it's a creature, it enters with two additional +1/+1 counters on it and has changeling.

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.)

Heidar, Rimewind Master

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

Coiling Oracle

When this creature enters, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

Spirit of the Aldergard

When this creature enters, search your library for a snow land card, reveal it, put it into your hand, then shuffle.
This creature gets +1/+0 for each other snow permanent you control.

Ohran Viper

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

Frost Augur

{S}, {T}: Look at the top card of your library. If it's a snow card, you may reveal it and put it into your hand. ({S} can be paid with one mana from a snow source.)

Boreal Druid

Priest of the Haunted Edge

{T}, Sacrifice this creature: Target creature gets -X/-X until end of turn, where X is the number of snow lands you control. Activate only as a sorcery.

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.

Icebreaker Kraken

Affinity for snow lands (This spell costs {1} less to cast for each snow land you control.)
When this creature enters, artifacts and creatures target opponent controls don't untap during that player's next untap step.
Return three snow lands you control to their owner's hand: Return this creature to its owner's hand.

Abominable Treefolk

Trample
Abominable Treefolk's power and toughness are each equal to the number of snow permanents you control.
When this creature enters, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Kaldring, the Rimestaff

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

Jorn, God of Winter

Whenever Jorn attacks, untap each snow permanent you control.

Jorn, God of Winter // Kaldring, the Rimestaff

Conifer Wurm

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

Rimewind Cryomancer

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

Sculptor of Winter

Pilfering Hawk

Flying
{S}, {T}: Draw a card, then discard a card. ({S} can be paid with one mana from a snow source.)

Ascendant Spirit

{S}{S}: This creature becomes a Spirit Warrior with base power and toughness 2/3.
{S}{S}{S}: If this creature 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 this creature 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."