Bloodline Pretender

Changeling (This card is every creature type.)
As Bloodline Pretender enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on Bloodline Pretender.

Captivating Unicorn

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

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters, destroy target artifact, enchantment, or land.

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Court of Ardenvale

When Court of Ardenvale enters, you become the monarch.
At the beginning of your upkeep, return target permanent card with mana value 3 or less from your graveyard to your hand. If you're the monarch, return that permanent card to the battlefield instead.

Cabaretti Courtyard

When Cabaretti Courtyard enters, sacrifice it. When you do, search your library for a basic Mountain, Forest, or Plains card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Good-Fortune Unicorn

Whenever another creature you control enters, put a +1/+1 counter on that creature.

Mana Tithe

Counter target spell unless its controller pays {1}.

Shelter

Target creature you control gains protection from the color of your choice until end of turn.
Draw a card.

Resurrection

Return target creature card from your graveyard to the battlefield.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Potion of Healing

When Potion of Healing enters, draw a card.
{W}, {T}, Sacrifice Potion of Healing: You gain 3 life.

On Serra's Wings

Enchant creature
Enchanted creature is legendary, gets +1/+1, and has flying, vigilance, and lifelink.

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.)

Cavalry Pegasus

Flying
Whenever Cavalry Pegasus attacks, each attacking Human gains flying until end of turn.

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.

Plains

Fall of the Impostor

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Put a +1/+1 counter on up to one target creature.
III — Exile a creature with the greatest power among creatures target opponent controls.

Celebrate the Harvest

Search your library for up to X basic land cards, where X is the number of different powers among creatures you control. Put those cards onto the battlefield tapped, then shuffle.

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.

Angel of Renewal

Flying
When Angel of Renewal enters, you gain 1 life for each creature you control.

Congregate

Target player gains 2 life for each creature on the battlefield.

Revitalize

Sol Ring

Sol Talisman

Suspend 3—{1} (Rather than cast this card from your hand, pay {1} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add {C}{C}.

Roaming Throne

Ward {2}
As Roaming Throne enters, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Avacyn's Pilgrim

Sigardian Paladin

As long as you've put one or more +1/+1 counters on a creature this turn, Sigardian Paladin has trample and lifelink.
{1}{G}{W}: Target creature you control with a +1/+1 counter on it gains trample and lifelink until end of turn.

Arcane Signet

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

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.

Arborea Pegasus

Flying
When Arborea Pegasus enters, target creature gets +1/+1 and gains flying until end of turn.

Majestic Auricorn

Mutate {3}{W} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Vigilance
Whenever this creature mutates, you gain 4 life.

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Ordeal of Heliod

Enchant creature
Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice Ordeal of Heliod.
When you sacrifice Ordeal of Heliod, you gain 10 life.

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Cooped Up

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

Canopy Vista

({T}: Add {G} or {W}.)
Canopy Vista enters tapped unless you control two or more basic lands.

Leyline of Sanctity

If Leyline of Sanctity is in your opening hand, you may begin the game with it on the battlefield.
You have hexproof. (You can't be the target of spells or abilities your opponents control.)

Glorious Anthem

Mesa Unicorn

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

Swords to Plowshares

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

Promising Vein

{T}: Add {C}.
{1}, {T}, Sacrifice Promising Vein: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Ghostly Prison

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Celestial Flare

Target player sacrifices an attacking or blocking creature of their choice.

Storm Herd

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

Brightmare

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

Rootborn Defenses

Populate. Creatures you control gain indestructible until end of turn. (To populate, create a token that's a copy of a creature token you control.)

Encircling Fissure

Prevent all combat damage that would be dealt this turn by creatures target opponent controls.
Awaken 2—{4}{W} (If you cast this spell for {4}{W}, also put two +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Fortified Village

As Fortified Village enters, you may reveal a Forest or Plains card from your hand. If you don't, Fortified Village enters tapped.
{T}: Add {G} or {W}.

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.)

Rescue the Foal

Exile target creature you control, then return that card to the battlefield under its owner's control. (Then exile this card. You may cast the creature later from exile.)

Pegasus Guardian

Flying
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, create a 1/1 white Pegasus creature token with flying.

Pegasus Guardian // Rescue the Foal

Selesnya Guildgate

This land enters tapped.
{T}: Add {G} or {W}.

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Opaline Unicorn

Sudden Salvation

Choose up to three target permanent cards in graveyards that were put there from the battlefield this turn. Return them to the battlefield tapped under their owners' control. You draw a card for each opponent who controls one or more of those permanents.

Park Heights Pegasus

Flying, trample
Whenever Park Heights Pegasus deals combat damage to a player, draw a card if you had two or more creatures enter the battlefield under your control this turn.

Ronom Unicorn

Sacrifice Ronom Unicorn: Destroy target enchantment.

Pacifism

Enchant creature
Enchanted creature can't attack or block.

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.

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.

Command Tower

Prized Unicorn

All creatures able to block Prized Unicorn do so.

Retreat to Kazandu

Landfall — Whenever a land you control enters, choose one —
• Put a +1/+1 counter on target creature.
• You gain 2 life.

Noble Quarry

Bestow {5}{G} (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 to a creature.)
All creatures able to block Noble Quarry or enchanted creature do so.
Enchanted creature gets +1/+1.

Forest

Resplendent Angel

Flying
At the beginning of each end step, if you gained 5 or more life this turn, create a 4/4 white Angel creature token with flying and vigilance.
{3}{W}{W}{W}: Until end of turn, Resplendent Angel gets +2/+2 and gains lifelink.

Daybreak Charger

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

Pegasus Courser

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

Evolving Wilds

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

Emiel the Blessed

{3}: Exile another target creature you control, then return it to the battlefield under its owner's control.
Whenever another creature you control enters, you may pay {G/W}. If you do, put a +1/+1 counter on it. If it's a Unicorn, put two +1/+1 counters on it instead. ({G/W} can be paid with either {G} or {W}.)

Inspiring Unicorn

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

Make a Stand

Creatures you control get +1/+0 and gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Temple of Plenty

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 {G} or {W}.

Banishing Light

When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield.

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.)

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.)

Selesnya Sanctuary

Selesnya Sanctuary enters tapped.
When Selesnya Sanctuary enters, return a land you control to its owner's hand.
{T}: Add {G}{W}.

Rider in Need

Create a 2/2 white Knight creature token with vigilance. (Then exile this card. You may cast the creature later from exile.)

Lonesome Unicorn

Lonesome Unicorn // Rider in Need

Sungrass Prairie

Light of Hope

Choose one —
• You gain 4 life.
• Destroy target enchantment.
• Put a +1/+1 counter on target creature.