Sol Ring

Consider

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

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Icingdeath, Frost Tyrant

Flying, vigilance
When Icingdeath, Frost Tyrant dies, create Icingdeath, Frost Tongue, a legendary white Equipment artifact token with "Equipped creature gets +2/+0," "Whenever equipped creature attacks, tap target creature defending player controls," and equip {2}.

Solitary Sanctuary

When this enchantment enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you tap an untapped creature an opponent controls, put a +1/+1 counter on target creature you control.

Succumb to the Cold

Tap one or two target creatures an opponent controls. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Frozen Solid

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

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.

Conifer Wurm

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

Frozen Aether

Artifacts, creatures, and lands your opponents control enter tapped.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

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.

Divine Reckoning

Each player chooses a creature they control. Destroy the rest.
Flashback {5}{W}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Hylda of the Icy Crown

Whenever you tap an untapped creature an opponent controls, you may pay {1}. When you do, choose one —
• Create a 4/4 white and blue Elemental creature token.
• Put a +1/+1 counter on each creature you control.
• Scry 2, then draw a card.

Command Tower

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

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.

Frostwalk Bastion

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

Glittering Frost

Enchant land
Enchanted land is snow.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Winter's Rest

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

Balduvian Frostwaker

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

Hylda's Crown of Winter

{1}, {T}: Tap target creature. This ability costs {1} less to activate during your turn.
{3}, Sacrifice Hylda's Crown of Winter: Draw a card for each tapped creature your opponents control.

Counterspell

Icewrought Sentry

Vigilance
Whenever this creature attacks, you may pay {1}{U}. When you do, tap target creature an opponent controls.
Whenever you tap an untapped creature an opponent controls, this creature gets +2/+1 until end of turn.

Farseek

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

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.)

Rage of Winter

Tap target creature. It doesn't untap during its controller's next untap step. (Then exile this card. You may cast the creature later from exile.)

Queen of Ice

Whenever this creature deals combat damage to a creature, tap that creature. It doesn't untap during its controller's next untap step.

Queen of Ice // Rage of Winter

Arcane Signet

Encase in Ice

Flash (You may cast this spell any time you could cast an instant.)
Enchant red or green creature
When this Aura enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Mystic Remora

Cumulative upkeep {1} (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 opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Whiteout

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

Wall of Frost

Defender
Whenever this creature blocks a creature, that creature doesn't untap during its controller's next untap step.

Sculptor of Winter

Rampant Growth

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

Rime Tender

{T}: Untap another target snow permanent.

Plunge into Winter

Tap up to one target creature. Scry 1, then draw a card.

Simic Signet

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.

Expel the Interlopers

Choose a number between 0 and 10. Destroy all creatures with power greater than or equal to the chosen number.

On Thin Ice

Enchant snow land you control
When this Aura enters, exile target creature an opponent controls until this Aura leaves the battlefield.

Snow-Covered Plains

Icy Manipulator

{1}, {T}: Tap target artifact, creature, or land.

Snowblind

Enchant creature
Enchanted creature gets -X/-Y. If that creature is attacking, X is the number of snow lands defending player controls. Otherwise, X is the number of snow lands its controller controls. Y is equal to X or to enchanted creature's toughness minus 1, whichever is smaller.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Frostveil Ambush

Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.
Cycling {1} ({1}, Discard this card: Draw a card.)

Freeze in Place

Tap target creature an opponent controls and put three stun counters on it. Scry 2. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Ice Out

Bargain (You may sacrifice an artifact, enchantment, or token as you cast this spell.)
This spell costs {1} less to cast if it's bargained.
Counter target spell.

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.

Snow-Covered Forest

Frost Breath

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

Harmonize

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Bitter Chill

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
When this Aura is put into a graveyard from the battlefield, you may pay {1}. If you do, scry 1, then draw a card.

Snow-Covered Island

Winter's Chill

Cast this spell only during combat before blockers are declared.
X can't be greater than the number of snow lands you control.
Choose X target attacking creatures. For each of those creatures, its controller may pay {1} or {2}. If that player doesn't, destroy that creature at end of combat. If that player pays only {1}, prevent all combat damage that would be dealt to and dealt by that creature this combat.

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.

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.

Azorius Signet

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.

Niblis of Frost

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Ice Floe

You may choose not to untap this land 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 this land remains tapped.

Ohran Frostfang

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

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.)

Kodama's Reach

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Explore

You may play an additional land this turn.
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.

Sharae of Numbing Depths

When Sharae enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you tap one or more untapped creatures your opponents control, draw a card. This ability triggers only once each turn.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.