Go for the Throat

Thought Devourer

Flying
Your maximum hand size is reduced by four.

Thought Vessel

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

Port of Karfell

Port of Karfell enters tapped.
{T}: Add {U}.
{3}{U}{B}{B}, {T}, Sacrifice Port of Karfell: Mill four cards, then return a creature card from your graveyard to the battlefield tapped. (To mill a card, put the top card of your library into your graveyard.)

Submerged Boneyard

Submerged Boneyard enters tapped.
{T}: Add {U} or {B}.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Rust Elemental

Flying
At the beginning of your upkeep, sacrifice an artifact other than Rust Elemental. If you can't, tap Rust Elemental and you lose 4 life.

Ice Tunnel

({T}: Add {U} or {B}.)
Ice Tunnel enters tapped.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

Negate

Dimir Aqueduct

Dimir Aqueduct enters tapped.
When Dimir Aqueduct enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Murder

Accursed Marauder

When Accursed Marauder enters, each player sacrifices a nontoken creature of their choice.

Grinning Demon

At the beginning of your upkeep, you lose 2 life.
Morph {2}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Dimir Guildgate

This land enters tapped.
{T}: Add {U} or {B}.

Exotic Orchard

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

Dismal Backwater

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {B}.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Swamp

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Arcane Signet

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

Tormented Soul

Tormented Soul can't block and can't be blocked.

Sol Ring

Dark Ritual

Serum Snare

Return target nonland permanent to its owner's hand. If that permanent had mana value 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sygg, River Cutthroat

At the beginning of each end step, if an opponent lost 3 or more life this turn, you may draw a card. (Damage causes loss of life.)

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.

Wretched Anurid

Whenever another creature enters, you lose 1 life.

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Jwar Isle Refuge

Jwar Isle Refuge enters tapped.
When Jwar Isle Refuge enters, you gain 1 life.
{T}: Add {U} or {B}.

Soured Springs

Soured Springs enters tapped.
When Soured Springs enters, it deals 1 damage to target opponent.
{T}: Add {U} or {B}.

Island

Counterspell

Sky Diamond

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Darkwater Catacombs

Tainted Isle

{T}: Add {C}.
{T}: Add {U} or {B}. Activate only if you control a Swamp.

Yukora, the Prisoner

When Yukora, the Prisoner leaves the battlefield, sacrifice all non-Ogre creatures you control.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Vraska's Fall

Each opponent sacrifices a creature or planeswalker of their choice and gets a poison counter.

Hasran Ogress

Whenever Hasran Ogress attacks, it deals 3 damage to you unless you pay {2}.

Jon Irenicus, Shattered One

At the beginning of your end step, target opponent gains control of up to one target creature you control. Put two +1/+1 counters on it and tap it. It's goaded for the rest of the game and it gains "This creature can't be sacrificed." (It attacks each combat if able and attacks a player other than you if able.)
Whenever a creature you own but don't control attacks, you draw a card.

Temple of Deceit

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {B}.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Plaguecrafter

When Plaguecrafter enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Mist-Cloaked Herald

Command Tower

Aetherize

Return all attacking creatures to their owner's hand.

Dispel

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Ebon Drake

Flying
Whenever a player casts a spell, you lose 1 life.

Slither Blade

Desecration Elemental

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever a player casts a spell, sacrifice a creature.

Master of the Feast

Flying
At the beginning of your upkeep, each opponent draws a card.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Filter Out

Return all noncreature, nonland permanents to their owners' hands.

Parasitic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, its controller loses 2 life and you gain 2 life.

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.