Frost Bite

Frost Bite deals 2 damage to target creature or planeswalker. If you control three or more snow permanents, it deals 3 damage instead.

Drift of the Dead

Defender (This creature can't attack.)
Drift of the Dead's power and toughness are each equal to the number of snow lands you control.

Rimewind Taskmage

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

Chilling Shade

Flying
{S}: Chilling Shade gets +1/+1 until end of turn. ({S} can be paid with one mana from a snow source.)

Balduvian Conjurer

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

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.)

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.

Iceberg Cancrix

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

Rime Tender

{T}: Untap another target snow permanent.

Pilfering Hawk

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

Goblin Rimerunner

{T}: Target creature can't block this turn.
{S}: Goblin Rimerunner gains haste until end of turn. ({S} can be paid with one mana from a snow source.)

Priest of the Haunted Edge

{T}, Sacrifice Priest of the Haunted Edge: Target creature gets -X/-X until end of turn, where X is the number of snow lands you control. Activate only as a sorcery.