Auriok Champion

Protection from black and from red
Whenever another creature enters, you may gain 1 life.

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Sanctum Prelate

As Sanctum Prelate enters, choose a number.
Noncreature spells with mana value equal to the chosen number can't be cast.

Aether Vial

At the beginning of your upkeep, you may put a charge counter on Aether Vial.
{T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Leyline of the Void

If Leyline of the Void is in your opening hand, you may begin the game with it on the battlefield.
If a card would be put into an opponent's graveyard from anywhere, exile it instead.

Noble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {G}, {W}, or {U}.

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Silent Clearing

{T}, Pay 1 life: Add {W} or {B}.
{1}, {T}, Sacrifice Silent Clearing: Draw a card.

General Kudro of Drannith

Other Humans you control get +1/+1.
Whenever General Kudro of Drannith or another Human you control enters, exile target card from an opponent's graveyard.
{2}, Sacrifice two Humans: Destroy target creature with power 4 or greater.

Palace Jailer

When Palace Jailer enters, you become the monarch.
When Palace Jailer enters, exile target creature an opponent controls until an opponent becomes the monarch.

Cavern of Souls

As Cavern of Souls enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Unclaimed Territory

As Unclaimed Territory enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Thalia, Guardian of Thraben

First strike
Noncreature spells cost {1} more to cast.

Thalia's Lieutenant

When Thalia's Lieutenant enters, put a +1/+1 counter on each other Human you control.
Whenever another Human you control enters, put a +1/+1 counter on Thalia's Lieutenant.

Mindbreak Trap

If an opponent cast three or more spells this turn, you may pay {0} rather than pay this spell's mana cost.
Exile any number of target spells.

Kitesail Freebooter

Flying
When Kitesail Freebooter enters, target opponent reveals their hand. You choose a noncreature, nonland card from it. Exile that card until Kitesail Freebooter leaves the battlefield.

Karakas

{T}: Add {W}.
{T}: Return target legendary creature to its owner's hand.

Meddling Mage

As Meddling Mage enters, choose a nonland card name.
Spells with the chosen name can't be cast.

Ancient Ziggurat

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Wasteland

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

Containment Priest

Flash
If a nontoken creature would enter and it wasn't cast, exile it instead.

Champion of the Parish

Whenever another Human enters under your control, put a +1/+1 counter on Champion of the Parish.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Reflector Mage

When Reflector Mage enters, return target creature an opponent controls to its owner's hand. That creature's owner can't cast spells with the same name as that creature until your next turn.

Greymond, Avacyn's Stalwart

As Greymond, Avacyn's Stalwart enters, choose two abilities from among first strike, vigilance, and lifelink.
Humans you control have each of the chosen abilities.
As long as you control four or more Humans, Humans you control get +2/+2.

Imperial Recruiter

When Imperial Recruiter enters, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.

Orzhov Pontiff

Haunt (When this creature dies, exile it haunting target creature.)
When Orzhov Pontiff enters or the creature it haunts dies, choose one —
• Creatures you control get +1/+1 until end of turn.
• Creatures you don't control get -1/-1 until end of turn.

Gregor, Shrewd Magistrate

Skulk (This creature can't be blocked by creatures with greater power.)
Whenever Gregor, Shrewd Magistrate deals combat damage to a player, draw cards equal to its power.

Horizon Canopy

{T}, Pay 1 life: Add {G} or {W}.
{1}, {T}, Sacrifice Horizon Canopy: Draw a card.

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.