Have

Dakkon Blackblade

Dakkon Blackblade's power and toughness are each equal to the number of lands you control.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Counterspell

Sword of Feast and Famine

Equipped creature gets +2/+2 and has protection from black and from green.
Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control.
Equip {2}

Expedition Map

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

Swords to Plowshares

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

Sol Ring

Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap this land for mana, target opponent creates a 1/1 colorless Spirit creature token.

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.)

Pendrell Mists

All creatures have "At the beginning of your upkeep, sacrifice this creature unless you pay {1}."

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Arcane Signet

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

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.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Sevinne's Reclamation

Return target permanent card with mana value 3 or less from your graveyard to the battlefield. If this spell was cast from a graveyard, you may copy this spell and may choose a new target for the copy.
Flashback {4}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Recruiter of the Guard

When this creature enters, you may search your library for a creature card with toughness 2 or less, reveal it, put it into your hand, then shuffle.

Admonition Angel

Flying
Landfall — Whenever a land you control enters, you may exile target nonland permanent other than this creature.
When this creature leaves the battlefield, return all cards exiled with it to the battlefield under their owners' control.

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.

Herald of Leshrac

Flying
Cumulative upkeep—Gain control of a land you don't control. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
This creature gets +1/+1 for each land you control but don't own.
When this creature leaves the battlefield, each player gains control of each land they own that you control.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Fierce Guardianship

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

Fabled Passage

{T}, Sacrifice this land: 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.

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.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Roil Elemental

Flying
Landfall — Whenever a land you control enters, you may gain control of target creature for as long as you control this creature.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

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.

Island of Wak-Wak

{T}: Target creature with flying has base power 0 until end of turn.

Lightning Greaves

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

Morphic Pool

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

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.

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.