Tithe

Search your library for a Plains card. If target opponent controls more lands than you, you may search your library for an additional Plains card. Reveal those cards, put them into your hand, then shuffle.

Razortide Bridge

Razortide Bridge enters tapped.
Indestructible
{T}: Add {W} or {U}.

Ancient Den

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice Strip Mine: Destroy target land.

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.

Spire of Industry

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Activate only if you control an artifact.

Saprazzan Skerry

Saprazzan Skerry enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Saprazzan Skerry: Add {U}{U}. If there are no depletion counters on Saprazzan Skerry, sacrifice it.

Land Tax

At the beginning of your upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Buried Ruin: Return target artifact card from your graveyard to your hand.

Sword of Hearth and Home

Equipped creature gets +2/+2 and has protection from green and from white.
Whenever equipped creature deals combat damage to a player, exile up to one target creature you own, then search your library for a basic land card. Put both cards onto the battlefield under your control, then shuffle.
Equip {2}

Castle Ardenvale

Castle Ardenvale enters tapped unless you control a Plains.
{T}: Add {W}.
{2}{W}{W}, {T}: Create a 1/1 white Human creature token.

Isolated Watchtower

{T}: Add {C}.
{2}, {T}: Scry 1, then you may reveal the top card of your library. If a basic land card is revealed this way, put it onto the battlefield tapped. Activate only if an opponent controls at least two more lands than you.

Soldevi Excavations

If Soldevi Excavations would enter, sacrifice an untapped Island instead. If you do, put Soldevi Excavations onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {C}{U}.
{1}, {T}: Scry 1.

Vesuva

You may have Vesuva enter tapped as a copy of any land on the battlefield.

Thawing Glaciers

Thawing Glaciers enters tapped.
{1}, {T}: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle. Return Thawing Glaciers to its owner's hand at the beginning of the next cleanup step.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Thespian's Stage

{T}: Add {C}.
{2}, {T}: Thespian's Stage becomes a copy of target land, except it has this ability.

Cartographer's Hawk

Flying
When Cartographer's Hawk deals combat damage to a player who controls more lands than you, return it to its owner's hand. If you do, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Kor Cartographer

When Kor Cartographer enters, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Minamo, School at Water's Edge

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

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.

Boreas Charger

Flying
When Boreas Charger leaves the battlefield, choose an opponent who controls more lands than you. Search your library for a number of Plains cards equal to the difference, reveal those cards, put one of them onto the battlefield tapped and the rest into your hand, then shuffle.

Loyal Warhound

Vigilance
When Loyal Warhound enters, if an opponent controls more lands than you, search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Mistveil Plains

({T}: Add {W}.)
Mistveil Plains enters tapped.
{W}, {T}: Put target card from your graveyard on the bottom of your library. Activate only if you control two or more white permanents.

Academy Ruins

{T}: Add {C}.
{1}{U}, {T}: Put target artifact card from your graveyard on top of your library.

Scorched Ruins

If Scorched Ruins would enter, sacrifice two untapped lands instead. If you do, put Scorched Ruins onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {C}{C}{C}{C}.

Karoo

Karoo enters tapped.
When Karoo enters, sacrifice it unless you return an untapped Plains you control to its owner's hand.
{T}: Add {C}{W}.

Irrigated Farmland

({T}: Add {W} or {U}.)
Irrigated Farmland enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Bant Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Bant Panorama: Search your library for a basic Forest, Plains, or Island card, put it onto the battlefield tapped, then shuffle.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Seat of the Synod

Treasure Vault

{T}: Add {C}.
{X}{X}, {T}, Sacrifice Treasure Vault: Create X Treasure tokens.

Stoic Farmer

When Stoic Farmer enters, search your library for a basic Plains card and reveal it. If an opponent controls more lands than you, put it onto the battlefield tapped. Otherwise, put it into your hand. Then shuffle.
Foretell {1}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Dust Bowl

{T}: Add {C}.
{3}, {T}, Sacrifice a land: Destroy target nonbasic land.

Tolaria West

Tolaria West enters tapped.
{T}: Add {U}.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with mana value 0, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Settle the Wreckage

Exile all attacking creatures target player controls. That player may search their library for that many basic land cards, put those cards onto the battlefield tapped, then shuffle.

Weathered Wayfarer

{W}, {T}: Search your library for a land card, reveal it, put it into your hand, then shuffle. Activate only if an opponent controls more lands than you.

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.

Coral Atoll

Coral Atoll enters tapped.
When Coral Atoll enters, sacrifice it unless you return an untapped Island you control to its owner's hand.
{T}: Add {C}{U}.

Serra's Sanctum

{T}: Add {W} for each enchantment you control.

Oreskos Explorer

When Oreskos Explorer enters, search your library for up to X Plains cards, where X is the number of players who control more lands than you. Reveal those cards, put them into your hand, then shuffle.

Remote Farm

Remote Farm enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Remote Farm: Add {W}{W}. If there are no depletion counters on Remote Farm, sacrifice it.

Keeper of the Accord

At the beginning of each opponent's end step, if that player controls more creatures than you, create a 1/1 white Soldier creature token.
At the beginning of each opponent's end step, if that player controls more lands than you, you may search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Flood Plain

Flood Plain enters tapped.
{T}, Sacrifice Flood Plain: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Archaeomancer's Map

When Archaeomancer's Map enters, search your library for up to two basic Plains cards, reveal them, put them into your hand, then shuffle.
Whenever a land an opponent controls enters, if that player controls more lands than you, you may put a land card from your hand onto the battlefield.

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Flagstones of Trokair

{T}: Add {W}.
When Flagstones of Trokair is put into a graveyard from the battlefield, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Hallowed Fountain

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

Tundra

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Raff Capashen, Ship's Mage

Flash
Flying
You may cast historic spells as though they had flash. (Artifacts, legendaries, and Sagas are historic.)

Kjeldoran Outpost

If Kjeldoran Outpost would enter, sacrifice a Plains instead. If you do, put Kjeldoran Outpost onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add {W}.
{1}{W}, {T}: Create a 1/1 white Soldier creature token.

Emeria, the Sky Ruin

Emeria, the Sky Ruin enters tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Esper Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Esper Panorama: Search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped, then shuffle.

Command Tower

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

Expedition Map

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

Knight of the White Orchid

First strike
When Knight of the White Orchid enters, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Lotus Vale

If Lotus Vale would enter, sacrifice two untapped lands instead. If you do, put Lotus Vale onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add three mana of any one color.

Lotus Field

Hexproof
Lotus Field enters tapped.
When Lotus Field enters, sacrifice two lands.
{T}: Add three mana of any one color.

Ancient Tomb

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

Surveyor's Scope

{T}, Exile Surveyor's Scope: Search your library for up to X basic land cards, where X is the number of players who control at least two more lands than you. Put those cards onto the battlefield, then shuffle.

Endless Horizons

When Endless Horizons enters, search your library for any number of Plains cards, exile them, then shuffle.
At the beginning of your upkeep, you may put a card you own exiled with Endless Horizons into your hand.

Gift of Estates

If an opponent controls more lands than you, search your library for up to three Plains cards, reveal them, put them into your hand, then shuffle.

Crystal Vein

{T}: Add {C}.
{T}, Sacrifice Crystal Vein: Add {C}{C}.

Prismatic Vista

{T}, Pay 1 life, Sacrifice Prismatic Vista: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Dreamscape Artist

{2}{U}, {T}, Discard a card, Sacrifice a land: Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.