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.

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.)

Princess Twilight Sparkle

Flying
Other Alicorns, Horses, Pegasi, Ponies, and Unicorns you control get +1/+1.
{W}{U}{B}{R}{G}: If you control Applejack, Fluttershy, Pinkie Pie, Rainbow Dash, and Rarity, everypony wins the game.

Stormfront Pegasus

Opaline Unicorn

Good-Fortune Unicorn

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

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.)

Bill the Pony

When Bill the Pony enters, create two Food tokens. (They're artifacts with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Sacrifice a Food: Until end of turn, target creature you control assigns combat damage equal to its toughness rather than its power.

Exotic Orchard

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

Armored Pegasus

Ordinary Pony

When this creature enters, you may exile target non-Horse creature you control that wasn't put onto the battlefield with this ability this turn, then return it to the battlefield under its owner's control.

Princess Luna

Flying
When this creature transforms into Princess Luna, choose up to six cards you own from outside the game with a moon in their art, then exile those cards. As long as those cards remain exiled, you may cast them, and your friends may cast them with your permission. (Gifts are appreciated.)

Nightmare Moon

Flying
As long as it's nighttime, Nightmare Moon gets +2/+2 and has menace.
{6}: Transform Nightmare Moon. Anypony may activate this ability or help pay the cost. When they do, they become your friend.

Nightmare Moon // Princess Luna

Mesa Unicorn

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

Motivated Pony

Trample, haste
Whenever Motivated Pony attacks, attacking creatures get +1/+1 until end of turn. If a Food entered under your control this turn, untap those creatures and they get an additional +2/+2 until end of turn.

Rarity

Rare and mythic rare spells you cast cost {1} less to cast.
{1}, {T}, Reveal a My Little Pony® toy you own: Until end of turn, another target creature gains protection from each color in that toy's coat, mane, and outfit.

Concordia Pegasus

Vine Mare

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Vine Mare can't be blocked by black creatures.

Zodiac Horse

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Sungrace Pegasus

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

Dwarven Pony

{1}{R}, {T}: Target Dwarf creature gains mountainwalk until end of turn. (It can't be blocked as long as defending player controls a Mountain.)

Goreclaw, Terror of Qal Sisma

Creature spells you cast with power 4 or greater cost {2} less to cast.
Whenever Goreclaw, Terror of Qal Sisma attacks, each creature you control with power 4 or greater gets +1/+1 and gains trample 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.)

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.

Shadowfax, Lord of Horses

Horses you control have haste. (They can attack and {T} as soon as they come under your control.)
Whenever Shadowfax, Lord of Horses attacks, you may put a creature card with lesser power from your hand onto the battlefield tapped and attacking.

Lathiel, the Bounteous Dawn

Lifelink
At the beginning of each end step, if you gained life this turn, distribute up to that many +1/+1 counters among any number of other target creatures.

Plague Mare

Plague Mare can't be blocked by white creatures.
When Plague Mare enters, creatures your opponents control get -1/-1 until end of turn.

Pegasus Courser

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

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.

Alms Collector

Flash
If an opponent would draw two or more cards, instead you and that player each draw a card.

Ronom Unicorn

Sacrifice Ronom Unicorn: Destroy target enchantment.

Celestial Unicorn

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

Lightning Mare

This spell can't be countered.
Lightning Mare can't be blocked by blue creatures.
{1}{R}: Lightning Mare gets +1/+0 until end of turn.

Surge Mare

Surge Mare can't be blocked by green creatures.
Whenever Surge Mare deals damage to an opponent, you may draw a card. If you do, discard a card.
{1}{U}: Surge Mare gets +2/-2 until end of turn.

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.

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.

Mesa Pegasus

Flying; banding (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Capashen Unicorn

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

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}.)

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.

Zebra Unicorn

Whenever Zebra Unicorn deals damage, you gain that much life.

Thundering Mightmare

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Thundering Mightmare is paired with another creature, each of those creatures has "Whenever an opponent casts a spell, put a +1/+1 counter on this creature."

Inspiring Unicorn

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