Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Tropical Island

Infiltration Lens

Whenever equipped creature becomes blocked by a creature, you may draw two cards.
Equip {1}

Seeker of Skybreak

Mask of Memory

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Field of the Dead

Field of the Dead enters tapped.
{T}: Add {C}.
Whenever Field of the Dead or another land you control enters, if you control seven or more lands with different names, create a 2/2 black Zombie creature token.

Rampaging Baloths

Trample
Landfall — Whenever a land you control enters, you may create a 4/4 green Beast creature token.

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have Phyrexian Metamorph enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Sigil of Valor

Whenever equipped creature attacks alone, it gets +1/+1 until end of turn for each other creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Tireless Provisioner

Landfall — Whenever a land you control enters, create a Food token or a Treasure token. (Food is an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life." Treasure is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Springheart Nantuko

Bestow {1}{G}
Enchanted creature gets +1/+1.
Landfall — Whenever a land you control enters, you may pay {1}{G} if Springheart Nantuko is attached to a creature you control. If you do, create a token that's a copy of that creature. If you didn't create a token this way, create a 1/1 green Insect creature token.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Lumra, Bellow of the Woods

Vigilance, reach
Lumra, Bellow of the Woods's power and toughness are each equal to the number of lands you control.
When Lumra enters, mill four cards. Then return all land cards from your graveyard to the battlefield tapped.

Fyndhorn Elves

Llanowar Elves

Barrow-Blade

Equipped creature gets +1/+1.
Whenever equipped creature blocks or becomes blocked by a creature, that creature loses all abilities until end of turn.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Yavimaya, Cradle of Growth

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

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Lavaspur Boots

Equipped creature gets +1/+0 and has haste and ward {1}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
Equip {1}

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Forest

Unctus, Grand Metatect

Other blue creatures you control have "Whenever this creature becomes tapped, draw a card, then discard a card."
Other artifact creatures you control get +1/+1.
{U/P}: Until end of turn, target creature you control becomes a blue artifact in addition to its other colors and types. Activate only as a sorcery. ({U/P} can be paid with either {U} or 2 life.)

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Paradise Mantle

Equipped creature has "{T}: Add one mana of any color."
Equip {1}

Birds of Paradise

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Nadu, Winged Wisdom

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand. This ability triggers only twice each turn."

Delighted Halfling

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell, and that spell can't be countered.

Lotus Cobra

Landfall — Whenever a land you control enters, add one mana of any color.

Island

Shuko

Equipped creature gets +1/+0.
Equip {0} ({0}: Attach to target creature you control. Equip only as a sorcery.)

Tatyova, Benthic Druid

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

Spellskite

{U/P}: Change a target of target spell or ability to Spellskite. ({U/P} can be paid with either {U} or 2 life.)

Tribute Mage

When Tribute Mage enters, you may search your library for an artifact card with mana value 2, reveal that card, put it into your hand, then shuffle.

Legolas's Quick Reflexes

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Untap target creature. Until end of turn, it gains hexproof, reach, and "Whenever this creature becomes tapped, it deals damage equal to its power to up to one target creature."

Adventuring Gear

Landfall — Whenever a land you control enters, equipped creature gets +2/+2 until end of turn.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Dreamroot Cascade

Dreamroot Cascade enters tapped unless you control two or more other lands.
{T}: Add {G} or {U}.

Transmute Artifact

Sacrifice an artifact. If you do, search your library for an artifact card. If that card's mana value is less than or equal to the sacrificed artifact's mana value, put it onto the battlefield. If it's greater, you may pay {X}, where X is the difference. If you do, put it onto the battlefield. If you don't, put it into its owner's graveyard. Then shuffle.

Zendikar's Roil

Landfall — Whenever a land you control enters, create a 2/2 green Elemental creature token.

Bristly Bill, Spine Sower

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature.
{3}{G}{G}: Double the number of +1/+1 counters on each creature you control.

Trophy Mage

When Trophy Mage enters, you may search your library for an artifact card with mana value 3, reveal it, put it into your hand, then shuffle.

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Evolution Sage

Landfall — Whenever a land you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Avenger of Zendikar

When Avenger of Zendikar enters, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land you control enters, you may put a +1/+1 counter on each Plant creature you control.

Minamo, School at Water's Edge

{T}: Add {U}.
{U}, {T}: Untap target legendary permanent.

Aphetto Alchemist

{T}: Untap target artifact or creature.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Gemstone Caverns

If Gemstone Caverns is in your opening hand and you're not the starting player, you may begin the game with Gemstone Caverns on the battlefield with a luck counter on it. If you do, exile a card from your hand.
{T}: Add {C}. If Gemstone Caverns has a luck counter on it, instead add one mana of any color.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Windswept Heath

{T}, Pay 1 life, Sacrifice Windswept Heath: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Waterlogged Grove

{T}, Pay 1 life: Add {G} or {U}.
{1}, {T}, Sacrifice Waterlogged Grove: Draw a card.

Gaea's Cradle

{T}: Add {G} for each creature you control.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters, you may pay 2 life. If you don't, it enters tapped.

March of Swirling Mist

As an additional cost to cast this spell, you may exile any number of blue cards from your hand. This spell costs {2} less to cast for each card exiled this way.
Up to X target creatures phase out. (While they're phased out, they're treated as though they don't exist. Each one phases in before its controller untaps during their next untap step.)

Flesh Duplicate

You may have Flesh Duplicate enter as a copy of any creature on the battlefield, except it has vanishing 3 if that creature doesn't have vanishing. (A permanent with vanishing 3 enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Misty Rainforest

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Sylvan Library

At the beginning of your draw step, you may draw two additional cards. If you do, choose two cards in your hand drawn this turn. For each of those cards, pay 4 life or put the card on top of your library.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Sylvan Safekeeper

Sacrifice a land: Target creature you control gains shroud until end of turn. (It can't be the target of spells or abilities.)

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Sol Ring

Tezzeret the Seeker

+1: Untap up to two target artifacts.
−X: Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.
−5: Artifacts you control become artifact creatures with base power and toughness 5/5 until end of turn.

Shifting Woodland

Shifting Woodland enters tapped unless you control a Forest.
{T}: Add {G}.
Delirium — {2}{G}{G}: Shifting Woodland becomes a copy of target permanent card in your graveyard until end of turn. Activate only if there are four or more card types among cards in your graveyard.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Rejuvenating Springs

Rejuvenating Springs enters tapped unless you have two or more opponents.
{T}: Add {G} or {U}.

Umbral Mantle

Equipped creature has "{3}, {Q}: This creature gets +2/+2 until end of turn." ({Q} is the untap symbol.)
Equip {0}

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Command Tower

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

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Thought Vessel

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Elvish Mystic

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Flooded Strand

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Scute Swarm

Landfall — Whenever a land you control enters, create a 1/1 green Insect creature token. If you control six or more lands, create a token that's a copy of Scute Swarm instead.