Myr Battlesphere

When Myr Battlesphere enters, create four 1/1 colorless Myr artifact creature tokens.
Whenever Myr Battlesphere attacks, you may tap X untapped Myr you control. If you do, Myr Battlesphere gets +X/+0 until end of turn and deals X damage to the player or planeswalker it's attacking.

Once Upon a Time

If this spell is the first spell you've cast this game, you may cast it without paying its mana cost.
Look at the top five cards of your library. You may reveal a creature or land card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Oath of Druids

At the beginning of each player's upkeep, that player chooses target player who controls more creatures than they do and is their opponent. The first player may reveal cards from the top of their library until they reveal a creature card. If the first player does, that player puts that card onto the battlefield and all other cards revealed this way into their graveyard.

Glacial Floodplain

({T}: Add {W} or {U}.)
Glacial Floodplain enters tapped.

Swords to Plowshares

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

Channel

Until end of turn, any time you could activate a mana ability, you may pay 1 life. If you do, add {C}.

Arctic Treeline

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

Prophetic Prism

When Prophetic Prism enters, draw a card.
{1}, {T}: Add one mana of any color.

Cloudpost

Cloudpost enters tapped.
{T}: Add {C} for each Locus on the battlefield.

Sol Ring

Snow-Covered Island

Breaker of Creation

When you cast this spell, you gain 1 life for each colorless permanent you control.
Hexproof from each color
Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)

Glimmerpost

When Glimmerpost enters, you gain 1 life for each Locus on the battlefield.
{T}: Add {C}.

Expedition Map

{2}, {T}, Sacrifice this artifact: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
Ulamog's Crusher attacks each combat if able.

Snow-Covered Plains

Sylvan Scrying

Search your library for a land card, reveal it, put it into your hand, then shuffle.

Tinker

As an additional cost to cast this spell, sacrifice an artifact.
Search your library for an artifact card, put that card onto the battlefield, then shuffle.

Rimewood Falls

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

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.

Shimmerdrift Vale

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