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.)

Rimewood Falls

({T}: Add {G} or {U}.)
Rimewood Falls enters tapped.

Snow-Covered Plains

Gelid Shackles

Enchant creature
Enchanted creature can't block, and its activated abilities can't be activated.
{S}: Enchanted creature gains defender until end of turn. ({S} can be paid with one mana from a snow source.)

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Counterspell

Ice Floe

You may choose not to untap Ice Floe during your untap step.
{T}: Tap target creature without flying that's attacking you. It doesn't untap during its controller's untap step for as long as Ice Floe remains tapped.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Conifer Wurm

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

Bant Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Bant Panorama: Search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle.

Felidar Retreat

Landfall — Whenever a land you control enters, choose one —
• Create a 2/2 white Cat Beast creature token.
• Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.

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.

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.)

Whiteout

All creatures lose flying until end of turn.
Sacrifice a snow land: Return Whiteout from your graveyard to your hand.

Simic Signet

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.

Arcum's Weathervane

{2}, {T}: Target snow land is no longer snow.
{2}, {T}: Target nonsnow basic land becomes snow.

Sunstone

{2}, Sacrifice a snow land: Prevent all combat damage that would be dealt this turn.

Wrath of God

Destroy all creatures. They can't be regenerated.

Tatyova, Benthic Druid

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

Bant Charm

Choose one —
• Destroy target artifact.
• Put target creature on the bottom of its owner's library.
• Counter target instant spell.

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.)

The Three Seasons

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Mill three cards.
II — Return up to two target snow permanent cards from your graveyard to your hand.
III — Choose three cards in each graveyard. Their owners shuffle those cards into their libraries.

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.)

Rime Tender

{T}: Untap another target snow permanent.

Brokers Hideout

When Brokers Hideout enters, sacrifice it. When you do, search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Icehide Golem

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

Return to Nature

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Growth Spiral

Draw a card. You may put a land card from your hand onto the battlefield.

Iceberg Cancrix

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

Crystallization

Enchant creature
Enchanted creature can't attack or block.
When enchanted creature becomes the target of a spell or ability, exile that creature.

Harmonize

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Joint Exploration

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Scry 2, then draw a card. If this spell was kicked, you may put a land card from your hand onto the battlefield.

Explorer's Scope

Whenever equipped creature attacks, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Squall Drifter

Icebreaker Kraken

This spell costs {1} less to cast for each snow land you control.
When Icebreaker Kraken 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 Icebreaker Kraken to its owner's hand.

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.)

Boreal Centaur

{S}: Boreal Centaur gets +1/+1 until end of turn. Activate only once each turn. ({S} can be paid with one mana from a snow source.)

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Snow-Covered Island

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

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.)

Sculptor of Winter

Shimmerdrift Vale

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

Birds of Paradise

Snow-Covered Forest

Icehide Troll

{S}{S}: Icehide Troll gets +2/+0 and gains indestructible until end of turn. Tap it. (Damage and effects that say "destroy" don't destroy it. {S} can be paid with one mana from a snow source.)

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Nissa, Steward of Elements

+2: Scry 2.
0: Look at the top card of your library. If it's a land card or a creature card with mana value less than or equal to the number of loyalty counters on Nissa, Steward of Elements, you may put that card onto the battlefield.
−6: Untap up to two target lands you control. They become 5/5 Elemental creatures with flying and haste until end of turn. They're still lands.

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.

Rampant Growth

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

Thirsting Roots

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Snowfall

Cumulative upkeep {U} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an Island is tapped for mana, its controller may add an additional {U}. If that Island is snow, its controller may add an additional {U}{U} instead. Spend this mana only to pay cumulative upkeep costs.

Cover of Winter

Cumulative upkeep {S} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it. {S} can be paid with one mana from a snow source.)
If a creature would deal combat damage to you and/or one or more creatures you control, prevent X of that damage, where X is the number of age counters on Cover of Winter.
{S}: Put an age counter on Cover of Winter.

Isu the Abominable

You may look at the top card of your library any time.
You may play snow lands and cast snow spells from the top of your library.
Whenever another snow permanent you control enters, you may pay {G}, {W}, or {U}. If you do, put a +1/+1 counter on Isu the Abominable.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Blizzard Brawl

Choose target creature you control and target creature you don't control. If you control three or more snow permanents, the creature you control gets +1/+0 and gains indestructible until end of turn. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Arctic Treeline

({T}: Add {G} or {W}.)
Arctic Treeline enters tapped.

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."

Glacial Revelation

Reveal the top six cards of your library. You may put any number of snow permanent cards from among them into your hand. Put the rest into your graveyard.

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.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Explore

You may play an additional land this turn.
Draw a card.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Moritte of the Frost

Changeling (This card is every creature type.)
You may have Moritte of the Frost 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.

Into the North

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

Vega, the Watcher

Flying
Whenever you cast a spell from anywhere other than your hand, draw a card.

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.)

Azorius Signet

Spirit of the Aldergard

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

Seaside Citadel

Seaside Citadel enters tapped.
{T}: Add {G}, {W}, or {U}.

Balduvian Frostwaker

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

Blessing of Frost

Distribute X +1/+1 counters among any number of creatures you control, where X is the amount of {S} spent to cast this spell. Then draw a card for each creature you control with power 4 or greater.