Balduvian Frostwaker

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

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.)

Frozen Aether

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

Blizzard Strix

Flash
Flying
When Blizzard Strix enters the battlefield, if you control another snow permanent, exile target permanent other than Blizzard Strix. Return that card to the battlefield under its owner's control at the beginning of the next end 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.)

Ice Tunnel

({T}: Add {U} or {B}.)
Ice Tunnel enters the battlefield tapped.

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 Queen of Ice 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

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.)

Frostwind Invoker

Flying
{8}: Creatures you control gain flying until end of turn.

Snow-Covered Forest

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.)

Woodland Chasm

({T}: Add {B} or {G}.)
Woodland Chasm enters the battlefield tapped.

Time of Ice

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Tap target creature an opponent controls. It doesn't untap during its controller's untap step for as long as you control Time of Ice.
III — Return all tapped creatures to their owners' hands.

Ojutai, Soul of Winter

Flying, vigilance
Whenever a Dragon you control attacks, tap target nonland permanent an opponent controls. That permanent doesn't untap during its controller's next untap step.

Frost Lynx

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

Frost Breath

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

Sculptor of Winter

Borrowing 100,000 Arrows

Draw a card for each tapped creature target opponent controls.

Iceberg Cancrix

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

Spirit of the Aldergard

When Spirit of the Aldergard enters the battlefield, 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.

Abominable Treefolk

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

Berg Strider

When Berg Strider enters the battlefield, tap target artifact or creature an opponent controls. If {S} was spent to cast this spell, that permanent doesn't untap during its controller's next untap step. ({S} is mana from a snow source.)

Enthralling Hold

Enchant creature
You can't choose an untapped creature as this spell's target as you cast it.
You control enchanted creature.

Betrayal

Enchant creature an opponent controls
Whenever enchanted creature becomes tapped, you draw a card.

Rimewood Falls

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

Snow-Covered Island

Into the North

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

Pilfering Hawk

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

Kaldring, the Rimestaff

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

Jorn, God of Winter

Whenever Jorn attacks, untap each snow permanent you control.

Jorn, God of Winter // Kaldring, the Rimestaff

Wall of Frost

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