Ronom Serpent

Ronom Serpent can't attack unless defending player controls a snow land.
When you control no snow lands, sacrifice Ronom Serpent.

Balduvian Conjurer

{T}: Target snow land becomes a 2/2 creature until end of turn. It's still a land.

Ice Over

Enchant artifact or creature
Enchanted permanent doesn't untap during its controller's untap step.

Rimewind Taskmage

{1}, {T}: You may tap or untap target permanent. Activate only if you control four or more snow permanents.

Deep Freeze

Enchant creature
Enchanted creature has base power and toughness 0/4, has defender, loses all other abilities, and is a blue Wall in addition to its other colors and types.

Glacial Stalker

Morph {4}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Glacial Crasher

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Glacial Crasher can't attack unless there is a Mountain on the battlefield.

Glacial Wall

Frost Raptor

Flying
{S}{S}: Frost Raptor gains shroud until end of turn. ({S} can be paid with one mana from a snow source. A creature with shroud can't be the target of spells or abilities.)

Boreal Elemental

Flying
Spells your opponents cast that target Boreal Elemental cost {2} more to cast.

Thermal Flux

Choose one —
• Target nonsnow permanent becomes snow until end of turn.
• Target snow permanent isn't snow until end of turn.
Draw a card at the beginning of the next turn's upkeep.

Rimewind Cryomancer

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

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Cold Storage

{3}: Exile target creature you control.
Sacrifice Cold Storage: Return each creature card exiled with Cold Storage to the battlefield under your control.

Wall of Frost

Defender
Whenever Wall of Frost blocks a creature, that creature 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.

Snow Devil

Enchant creature
Enchanted creature has flying.
Enchanted creature has first strike as long as it's blocking and you control a snow land.

Frozen Solid

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
When enchanted creature is dealt damage, destroy it.

Frost Lynx

When Frost Lynx enters, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Uncomfortable Chill

Creatures your opponents control get -2/-0 until end of turn.
Draw a card.

Frost Breath

Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Ice Cage

Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated.
When enchanted creature becomes the target of a spell or ability, destroy Ice Cage.

Martyr of Frost

{2}, Reveal X blue cards from your hand, Sacrifice Martyr of Frost: Counter target spell unless its controller pays {X}.

Winter's Rest

Enchant creature
When Winter's Rest enters, tap enchanted creature.
As long as you control another snow permanent, enchanted creature doesn't untap during its controller's untap step.

Crippling Chill

Tap target creature. It doesn't untap during its controller's next untap step.
Draw a card.

Clairvoyance

Look at target player's hand.
Draw a card at the beginning of the next turn's upkeep.

Iceberg Cancrix

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

Rush of Ice

Tap target creature. It doesn't untap during its controller's next untap step.
Awaken 3—{4}{U} (If you cast this spell for {4}{U}, also put three +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Early Frost

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Snow-Covered Island

Icy Prison

When Icy Prison enters, exile target creature.
At the beginning of your upkeep, sacrifice Icy Prison unless any player pays {3}.
When Icy Prison leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Ojutai's Breath

Tap target creature. It doesn't untap during its controller's next untap step.
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.)

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.