Plains

Thurid, Mare of Destiny

Flying, lifelink
Whenever you cast a Pegasus, Unicorn, or Horse creature spell, copy it. (The copy becomes a token.)
Other Pegasi, Unicorns, and Horses you control get +1/+1.

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Loyal Unicorn

Vigilance
Lieutenant — At the beginning of combat on your turn, if you control your commander, prevent all combat damage that would be dealt to creatures you control this turn. Other creatures you control gain vigilance until end of turn.

Loyal Pegasus

Flying
Loyal Pegasus can't attack or block alone.

Shepherd of the Clouds

Flying, vigilance
When Shepherd of the Clouds enters, return target permanent card with mana value 3 or less from your graveyard to your hand. Return that card to the battlefield instead if you control a Mount.

Storm Herd

Create X 1/1 white Pegasus creature tokens with flying, where X is your life total.

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Caduceus, Staff of Hermes

Equipped creature has lifelink.
As long as you have 30 or more life, equipped creature gets +5/+5 and has indestructible and "Prevent all damage that would be dealt to this creature."
Equip {W}{W}

Secret Rendezvous

You and target opponent each draw three cards.

Plated Pegasus

Flash (You may cast this spell any time you could cast an instant.)
Flying
If a spell would deal damage to a permanent or player, prevent 1 damage that spell would deal to that permanent or player.

Capashen Unicorn

{1}{W}, {T}, Sacrifice Capashen Unicorn: Destroy target artifact or enchantment.

Reprieve

Return target spell to its owner's hand.
Draw a card.

Flowering of the White Tree

Legendary creatures you control get +2/+1 and have ward {1}.
Nonlegendary creatures you control get +1/+1.

Rebuff the Wicked

Counter target spell that targets a permanent you control.

Marble Diamond

Marble Diamond enters tapped.
{T}: Add {W}.

Captivating Unicorn

Constellation — Whenever an enchantment you control enters, tap target creature an opponent controls.

Inspiring Unicorn

Whenever Inspiring Unicorn attacks, creatures you control get +1/+1 until end of turn.

Keleth, Sunmane Familiar

Whenever a commander you control attacks, put a +1/+1 counter on it.
Partner (You can have two commanders if both have partner.)

Archaeomancer's Map

When Archaeomancer's Map 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.

Brightmare

When Brightmare enters, tap up to one target creature. You gain life equal to that creature's power.

Luminous Rebuke

This spell costs {3} less to cast if it targets a tapped creature.
Destroy target creature.

Idol of Oblivion

{T}: Draw a card. Activate only if you created a token this turn.
{8}, {T}, Sacrifice Idol of Oblivion: Create a 10/10 colorless Eldrazi creature token.

Steadfast Unicorn

{3}{W}: Creatures you control get +1/+1 and gain vigilance until end of turn. Activate only during your turn. (Attacking doesn't cause them to tap.)

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Opaline Unicorn

Brave the Elements

Choose a color. White creatures you control gain protection from the chosen color until end of turn.

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Shield Mare

Shield Mare can't be blocked by red creatures.
When Shield Mare enters or becomes the target of a spell or ability an opponent controls, you gain 3 life.

Cut a Deal

Each opponent draws a card, then you draw a card for each opponent who drew a card this way.

Pegasus Charger

Flying (This creature can't be blocked except by creatures with flying or reach.)
First strike (This creature deals combat damage before creatures without first strike.)

Leyline of Hope

If Leyline of Hope is in your opening hand, you may begin the game with it on the battlefield.
If you would gain life, you gain that much life plus 1 instead.
As long as you have at least 7 life more than your starting life total, creatures you control get +2/+2.

Song of the Worldsoul

Whenever you cast a spell, populate. (Create a token that's a copy of a creature token you control.)

Sunmane Pegasus

Flying
{1}{W}: Sunmane Pegasus gains vigilance and lifelink until end of turn. (Attacking doesn't cause it to tap. Damage dealt by it also causes you to gain that much life.)

Valorous Steed

Vigilance (Attacking doesn't cause this creature to tap.)
When Valorous Steed enters, create a 2/2 white Knight creature token with vigilance.

Prop Room

Untap each creature you control during each other player's untap step.
(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.)

Dazzling Theater

Creature spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a creature spell pays for {1} or one mana of that creature's color.)
(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.)

Dazzling Theater // Prop Room

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.

Neighborhood Guardian

Whenever another creature you control with power 2 or less enters, target creature you control gets +1/+1 until end of turn.

True Conviction

Creatures you control have double strike and lifelink.

Splendor Mare

Lifelink
Cycling {1}{W} ({1}{W}, Discard this card: Draw a card.)
When you cycle Splendor Mare, put a lifelink counter on target creature you control.

Regal Bunnicorn

Regal Bunnicorn's power and toughness are each equal to the number of nonland permanents you control.

Ronom Unicorn

Sacrifice Ronom Unicorn: Destroy target enchantment.

Celestial Unicorn

Whenever you gain life, put a +1/+1 counter on Celestial Unicorn.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Valkyrie's Call

Whenever a nontoken, non-Angel creature you control dies, return that card to the battlefield under its owner's control with a +1/+1 counter on it. It has flying and is an Angel in addition to its other types.

Farewell

Choose one or more —
• Exile all artifacts.
• Exile all creatures.
• Exile all enchantments.
• Exile all graveyards.

Phyrexian Pegasus

Flying
Whenever Phyrexian Pegasus attacks, another target attacking creature without flying gains flying until end of turn.

Boreas Charger

Flying
When Boreas Charger 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.

Sungrace Pegasus

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Crested Sunmare

Other Horses you control have indestructible.
At the beginning of each end step, if you gained life this turn, create a 5/5 white Horse creature token.

Sol Ring

Pearl Medallion

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

Diamond Mare

As Diamond Mare enters, choose a color.
Whenever you cast a spell of the chosen color, you gain 1 life.

Honor of the Pure

Gauntlet of Power

As Gauntlet of Power enters, choose a color.
Creatures of the chosen color get +1/+1.
Whenever a basic land is tapped for mana of the chosen color, its controller adds an additional one mana of that color.

Starnheim Courser

Flying
Artifact and enchantment spells you cast cost {1} less to cast.

Blessed Sanctuary

Prevent all noncombat damage that would be dealt to you and creatures you control.
Whenever a nontoken creature you control enters, create a 2/2 white Unicorn creature token.

Pegasus Courser

Flying
Whenever Pegasus Courser attacks, another target attacking creature gains flying until end of turn.

Mesa Unicorn

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Emeria, the Sky Ruin

Emeria, the Sky Ruin enters tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

Reliquary Tower

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

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Daybreak Charger

When Daybreak Charger enters, target creature gets +2/+0 until end of turn.

Nyxborn Unicorn

Bestow {3}{W} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Enchanted creature gets +2/+2 and has mentor.

Trusted Pegasus

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever Trusted Pegasus attacks, target attacking creature without flying gains flying until end of turn.