Conifer Wurm

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

Frostwalla

{S}: Frostwalla gets +2/+2 until end of turn. Activate only once each turn. ({S} can be paid with one mana from a snow source.)

Abominable Treefolk

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

Snow-Covered Island

Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Just the Wind

Return target creature to its owner's hand.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Snow-Covered Plains

Vizier of Tumbling Sands

{T}: Untap another target permanent.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When you cycle Vizier of Tumbling Sands, untap target permanent.

Very Cryptic Command

Choose two —
• Counter target black-bordered spell.
• Return target creature to its owner's hand.
• Untap each permanent you control with a watermark.
• Roll two six-sided dice. Target player mills X cards, where X is the total of those results.

Sacrifice Play

A person outside the game chooses an attacking or blocking creature target opponent controls. That player sacrifices that creature.

Emerge Unscathed

Target creature you control gains protection from the color of your choice until end of turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

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.

Heidar, Rimewind Master

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

Icehide Golem

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

Boreal Druid

Frostwalk Bastion

{T}: Add {C}.
{1}{S}: Until end of turn, Frostwalk Bastion becomes a 2/3 Construct artifact creature. It's still a land. ({S} can be paid with one mana from a snow source.)
Whenever Frostwalk Bastion deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Chillerpillar

{4}{S}{S}: Monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous. {S} can be paid with one mana from a snow source.)
As long as Chillerpillar is monstrous, it has flying.

GO TO JAIL

When GO TO JAIL enters, exile target creature an opponent controls until GO TO JAIL leaves the battlefield.
At the beginning of the upkeep of the exiled card's owner, that player rolls two six-sided dice. If they roll doubles, sacrifice GO TO JAIL.

Diamond Faerie

Flying
{1}{S}: Snow creatures you control get +1/+1 until end of turn. ({S} can be paid with one mana from a snow source.)

Balduvian Frostwaker

{U}, {T}: Target snow land becomes a 2/2 blue Elemental creature with flying. It's still a land.

Rime Tender

{T}: Untap another target snow permanent.

B.O.B. (Bevy of Beebles)

As B.O.B. enters, create four 1/1 blue Beeble creature tokens.
The number of loyalty counters on B.O.B. is equal to the number of Beebles you control. (Create or sacrifice Beebles whenever B.O.B. gains or loses loyalty.)
+1: Up to X target Beebles can't be blocked this turn, where X is the number of cards in your hand.
−1: Draw a card.

Boreal Shelf

Boreal Shelf enters tapped.
{T}: Add {W} or {U}.

Snow-Covered Forest

Arcum's Astrolabe

({S} can be paid with one mana from a snow source.)
When Arcum's Astrolabe enters, draw a card.
{1}, {T}: Add one mana of any color.

Coldsteel Heart

Coldsteel Heart enters tapped.
As Coldsteel Heart enters, choose a color.
{T}: Add one mana of the chosen color.