Cartographer's Hawk

Flying
When this creature 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.

Linvala, the Preserver

Flying
When Linvala enters, if an opponent has more life than you, you gain 5 life.
When Linvala enters, if an opponent controls more creatures than you, create a 3/3 white Angel creature token with flying.

Pulse of the Tangle

Create a 3/3 green Beast creature token. Then if an opponent controls more creatures than you, return Pulse of the Tangle to its owner's hand.

Battle Angels of Tyr

Flying, myriad
Whenever this creature deals combat damage to a player, draw a card if that player has more cards in hand than each other player. Then you create a Treasure token if that player controls more lands than each other player. Then you gain 3 life if that player has more life than each other player.

Loyal Warhound

Vigilance
When this creature 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.

Beza, the Bounding Spring

When Beza enters, create a Treasure token if an opponent controls more lands than you. You gain 4 life if an opponent has more life than you. Create two 1/1 blue Fish creature tokens if an opponent controls more creatures than you. Draw a card if an opponent has more cards in hand than you.

Veteran Soldier

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, for each opponent, create a 1/1 white Soldier creature token that's tapped and attacking that opponent."

Garruk, Unleashed

+1: Up to one target creature gets +3/+3 and gains trample until end of turn.
−2: Create a 3/3 green Beast creature token. Then if an opponent controls more creatures than you, put a loyalty counter on Garruk.
−7: You get an emblem with "At the beginning of your end step, you may search your library for a creature card, put it onto the battlefield, then shuffle."

Scouting Hawk

Flying
Keen Sight — When this creature 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.

Knight of the White Orchid

First strike
When this creature 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.

Aerial Surveyor

Flying
Whenever this Vehicle attacks, if defending player controls more lands than you, search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.
Crew 2

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.

Boreas Charger

Flying
When this creature 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.

Sunset Revelry

If an opponent has more life than you, you gain 4 life.
If an opponent controls more creatures than you, create two 1/1 white Human creature tokens.
If an opponent has more cards in hand than you, draw a card.

Discerning Financier

At the beginning of your upkeep, if an opponent controls more lands than you, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
{2}{W}: Choose another player. That player gains control of target Treasure you control. You draw a card.

Pulse of the Fields

You gain 4 life. Then if an opponent has more life than you, return Pulse of the Fields to its owner's hand.

Ward of Bones

Each opponent who controls more creatures than you can't cast creature spells. The same is true for artifacts and enchantments.
Each opponent who controls more lands than you can't play lands.

Archaeomancer's Map

When this artifact 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.

Sand Scout

When this creature enters, if an opponent controls more lands than you, search your library for a Desert card, put it onto the battlefield tapped, then shuffle.
Whenever one or more land cards are put into your graveyard from anywhere, create a 1/1 red, green, and white Sand Warrior creature token. This ability triggers only once each turn.

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.

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.

Damping Engine

A player who controls more permanents than each other player can't play lands or cast artifact, creature, or enchantment spells. That player may sacrifice a permanent of their choice for that player to ignore this effect until end of turn.

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.

Verge Rangers

First strike
You may look at the top card of your library any time.
As long as an opponent controls more lands than you, you may play lands from the top of your library. (You can play a land this way only if you have an available land play remaining.)

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.

Scholar of New Horizons

This creature enters with a +1/+1 counter on it.
{T}, Remove a counter from a permanent you control: Search your library for a Plains card and reveal it. If an opponent controls more lands than you, you may put that card onto the battlefield tapped. If you don't put the card onto the battlefield, put it into your hand. Then shuffle.

Keeper of the Beasts

{G}, {T}: Choose target opponent who controls more creatures than you do as you activate this ability. Create a 2/2 green Beast creature token.

Oreskos Explorer

When this creature 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.

Hardy Outlander

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, another target creature you control gets +X/+X until end of turn, where X is this creature's power."

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.

Priest of the Blessed Graf

At the beginning of your end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of opponents who control more lands than you.

Keeper of the Light

{W}, {T}: Choose target opponent who has more life than you do as you activate this ability. You gain 3 life.

Claim Jumper

Vigilance
When this creature enters, if an opponent controls more lands than you, you may search your library for a Plains card and put it onto the battlefield tapped. Then if an opponent controls more lands than you, repeat this process once. If you search your library this way, shuffle.

Avatar of Might

If an opponent controls at least four more creatures than you, this spell costs {6} less to cast.
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)