Opportunity

Flash of Insight

Look at the top X cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
Flashback—{1}{U}, Exile X blue cards from your graveyard. (You may cast this card from your graveyard for its flashback cost, then exile it. You can't exile Flash of Insight to pay for its own flashback cost.)

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Forbid

Buyback—Discard two cards. (You may discard two cards in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Counter target spell.

Abundance

If you would draw a card, you may instead choose land or nonland and reveal cards from the top of your library until you reveal a card of the chosen kind. Put that card into your hand and put all other cards revealed this way on the bottom of your library in any order.

Turnabout

Choose artifact, creature, or land. Tap all untapped permanents of the chosen type target player controls, or untap all tapped permanents of that type that player controls.

Naturalize

Reprocess

Sacrifice any number of artifacts, creatures, and/or lands. Draw a card for each permanent sacrificed this way.

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Necromancy

You may cast Necromancy as though it had flash. If you cast it any time a sorcery couldn't have been cast, the controller of the permanent it becomes sacrifices it at the beginning of the next cleanup step.
When Necromancy enters, if it's on the battlefield, it becomes an Aura with "enchant creature put onto the battlefield with Necromancy." Put target creature card from a graveyard onto the battlefield under your control and attach Necromancy to it. When Necromancy leaves the battlefield, that creature's controller sacrifices it.

Rewind

Counter target spell. Untap up to four lands.

Snow-Covered Swamp

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

Misdirection

You may exile a blue card from your hand rather than pay this spell's mana cost.
Change the target of target spell with a single target.

Stroke of Genius

Insidious Dreams

As an additional cost to cast this spell, discard X cards.
Search your library for X cards, then shuffle and put those cards on top in any order.

Dominate

Gain control of target creature with mana value X or less.

Slaughter

Buyback—Pay 4 life. (You may pay 4 life in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Destroy target nonblack creature. It can't be regenerated.

Deep Reconnaissance

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
Flashback {4}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Pulse of Llanowar

If a basic land you control is tapped for mana, it produces mana of a color of your choice instead of any other type.

Submerge

If an opponent controls a Forest and you control an Island, you may cast this spell without paying its mana cost.
Put target creature on top of its owner's library.

Kaldring, the Rimestaff

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

Jorn, God of Winter

Whenever Jorn attacks, untap each snow permanent you control.

Jorn, God of Winter // Kaldring, the Rimestaff

Crypt Rats

{X}: Crypt Rats deals X damage to each creature and each player. Spend only black mana on X.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Boomerang

Return target permanent to its owner's hand.

Reins of Power

Untap all creatures you control and all creatures target opponent controls. You and that opponent each gain control of all creatures the other controls until end of turn. Those creatures gain haste until end of turn.

Elsewhere Flask

When Elsewhere Flask enters, draw a card.
Sacrifice Elsewhere Flask: Choose a basic land type. Each land you control becomes that type until end of turn.

Back to Basics

Nonbasic lands don't untap during their controllers' untap steps.

Snow-Covered Forest

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

Rampant Growth

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

Llanowar Dead

Frantic Search

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

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Llanowar Elves

Chamber of Manipulation

Enchant land
Enchanted land has "{T}, Discard a card: Gain control of target creature until end of turn."

Predict

Choose a card name, then target player mills a card. If a card with the chosen name was milled this way, you draw two cards. Otherwise, you draw a card.

Blanket of Night

Each land is a Swamp in addition to its other land types.

Counterspell

Dark Ritual

Prevent all combat damage that would be dealt this turn.

Early Harvest

Target player untaps all basic lands they control.

Constant Mists

Buyback—Sacrifice a land. (You may sacrifice a land in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Prevent all combat damage that would be dealt this turn.

Annihilate

Destroy target nonblack creature. It can't be regenerated.
Draw a card.

Rain of Filth

Until end of turn, lands you control gain "Sacrifice this land: Add {B}."

Burgeoning

Whenever an opponent plays a land, you may put a land card from your hand onto the battlefield.

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Lim-Dûl's Vault

Look at the top five cards of your library. As many times as you choose, you may pay 1 life, put those cards on the bottom of your library in any order, then look at the top five cards of your library. Then shuffle and put the last cards you looked at this way on top in any order.

New Frontiers

Each player may search their library for up to X basic land cards and put them onto the battlefield tapped. Then each player who searched their library this way shuffles.

Expunge

Destroy target nonartifact, nonblack creature. It can't be regenerated.
Cycling {2} ({2}, Discard this card: Draw a card.)

Cadaverous Bloom

Exile a card from your hand: Add {B}{B} or {G}{G}.

Snow-Covered Island

Tangle

Prevent all combat damage that would be dealt this turn.
Each attacking creature doesn't untap during its controller's next untap step.

Ensnare

You may return two Islands you control to their owner's hand rather than pay this spell's mana cost.
Tap all creatures.

Desertion

Counter target spell. If an artifact or creature spell is countered this way, put that card onto the battlefield under your control instead of into its owner's graveyard.

Scrivener

When Scrivener enters, you may return target instant card from your graveyard to your hand.

Ponder

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

Relearn

Return target instant or sorcery card from your graveyard to your hand.

Breathstealer's Crypt

If a player would draw a card, instead they draw a card and reveal it. If it's a creature card, that player discards it unless they pay 3 life.

Necrologia

Cast this spell only during your end step.
As an additional cost to cast this spell, pay X life.
Draw X cards.

Corrupt

Corrupt deals damage to any target equal to the number of Swamps you control. You gain life equal to the damage dealt this way.