Cooped Up

Enchant creature
Enchanted creature can't attack or block.
{2}{W}: Exile enchanted creature.

Propaganda

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

Counterspell

Black Market Connections

At the beginning of your first main phase, choose one or more —
• Sell Contraband — Create a Treasure token. You lose 1 life.
• Buy Information — Draw a card. You lose 2 life.
• Hire a Mercenary — Create a 3/2 colorless Shapeshifter creature token with changeling. You lose 3 life. (It is every creature type.)

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Island

K'rrik, Son of Yawgmoth

({B/P} can be paid with either {B} or 2 life.)
Lifelink
For each {B} in a cost, you may pay 2 life rather than pay that mana.
Whenever you cast a black spell, put a +1/+1 counter on K'rrik.

Plains

Shipwreck Marsh

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Pearl Medallion

White spells you cast cost {1} less to cast.

Authority of the Consuls

Creatures your opponents control enter tapped.
Whenever a creature an opponent controls enters, you gain 1 life.

Leshrac's Sigil

Whenever an opponent casts a green spell, you may pay {B}{B}. If you do, look at that player's hand and choose a card from it. The player discards that card.
{B}{B}: Return this enchantment to its owner's hand.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: This artifact deals 50 damage to any target.

Thought Vessel

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

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Jet Medallion

Black spells you cast cost {1} less to cast.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Command Tower

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

Unstoppable Slasher

Deathtouch
Whenever this creature deals combat damage to a player, they lose half their life, rounded up.
When this creature dies, if it had no counters on it, return it to the battlefield tapped under its owner's control with two stun counters on it.

Vault of Champions

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

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Zur the Enchanter

Flying
Whenever Zur attacks, you may search your library for an enchantment card with mana value 3 or less, put it onto the battlefield, then shuffle.

Swamp

Godless Shrine

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

Morphic Pool

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

Fractured Realm

If a triggered ability of a permanent you control triggers, that ability triggers an additional time.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Mirror Room

When you unlock this door, create a token that's a copy of target creature you control, except it's a Reflection in addition to its other creature types.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)