Pledge of Unity

Put a +1/+1 counter on each creature you control. You gain 1 life for each creature you control.

Soul Warden

Whenever another creature enters, you gain 1 life.

Opaline Unicorn

Conclave Mentor

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 that creature instead.
When Conclave Mentor dies, you gain life equal to its power.

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.

Ajani Steadfast

+1: Until end of turn, up to one target creature gets +1/+1 and gains first strike, vigilance, and lifelink.
−2: Put a +1/+1 counter on each creature you control and a loyalty counter on each other planeswalker you control.
−7: You get an emblem with "If a source would deal damage to you or a planeswalker you control, prevent all but 1 of that damage."

Fountain of Renewal

At the beginning of your upkeep, you gain 1 life.
{3}, Sacrifice Fountain of Renewal: Draw a card.

Congregate

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

Plains

Storm Herd

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

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.

Cleric Class

(Gain the next level as a sorcery to add its ability.)
If you would gain life, you gain that much life plus 1 instead.
{3}{W}: Level 2
Whenever you gain life, put a +1/+1 counter on target creature you control.
{4}{W}: Level 3
When this Class becomes level 3, return target creature card from your graveyard to the battlefield. You gain life equal to that creature's toughness.

Daybreak Charger

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

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.

The Ozolith

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.
At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Nykthos Paragon

Whenever you gain life, you may put that many +1/+1 counters on each creature you control. Do this only once each turn.

Ronom Unicorn

Sacrifice Ronom Unicorn: Destroy target enchantment.

Ajani, Wise Counselor

+2: You gain 1 life for each creature you control.
−3: Creatures you control get +2/+2 until end of turn.
−9: Put X +1/+1 counters on target creature, where X is your life total.

Command Tower

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

Sol Ring

Good-Fortune Unicorn

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

Celestial Unicorn

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

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Adaptive Automaton

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Zebra Unicorn

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

Benevolent Unicorn

If a spell would deal damage to a permanent or player, it deals that much damage minus 1 to that permanent or player instead.

Mirari's Wake

Creatures you control get +1/+1.
Whenever you tap a land for mana, add one mana of any type that land produced.

Harmonize

Pristine Talisman

Metallic Mimic

As Metallic Mimic enters, choose a creature type.
Metallic Mimic is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

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}.)

Gavony Township

{T}: Add {C}.
{2}{G}{W}, {T}: Put a +1/+1 counter on each creature you control.

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.

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Revered Unicorn

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When Revered Unicorn leaves the battlefield, you gain life equal to the number of age counters on it.

Inspiring Call

Draw a card for each creature you control with a +1/+1 counter on it. Those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

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.

Prized Unicorn

All creatures able to block Prized Unicorn do so.

Brightmare

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

Irregular Cohort

Changeling (This card is every creature type.)
When Irregular Cohort enters, create a 2/2 colorless Shapeshifter creature token with changeling.

Distinguished Conjurer

Whenever another creature you control enters, you gain 1 life.
{4}{W}, {T}: Exile another target creature you control, then return it to the battlefield under its owner's control.

Inspiring Unicorn

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

Revitalize

Essence Warden

Forest

Branching Evolution

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

Mesa Unicorn

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

Ajani, Mentor of Heroes

+1: Distribute three +1/+1 counters among one, two, or three target creatures you control.
+1: Look at the top four cards of your library. You may reveal an Aura, creature, or planeswalker card from among them and put it into your hand. Put the rest on the bottom of your library in any order.
−8: You gain 100 life.

Cosmos Elixir

At the beginning of your end step, draw a card if your life total is greater than your starting life total. Otherwise, you gain 2 life.

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.)

Capashen Unicorn

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

Sapseep Forest

({T}: Add {G}.)
Sapseep Forest enters tapped.
{G}, {T}: You gain 1 life. Activate only if you control two or more green permanents.

Abzan Battle Priest

Outlast {W} ({W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has lifelink.

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.

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.

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.

Blighted Steppe

{T}: Add {C}.
{3}{W}, {T}, Sacrifice Blighted Steppe: You gain 2 life for each creature you control.

Arcane Signet

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.

Ajani, Inspiring Leader

+2: You gain 2 life. Put two +1/+1 counters on up to one target creature.
−3: Exile target creature. Its controller gains 2 life.
−10: Creatures you control gain flying and double strike until end of turn.

Kabira Crossroads

Kabira Crossroads enters tapped.
When Kabira Crossroads enters, you gain 2 life.
{T}: Add {W}.

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.

Wishmonger

{2}: Target creature gains protection from the color of its controller's choice until end of turn. Any player may activate this ability.

Selesnya Signet

Ajani Goldmane

+1: You gain 2 life.
−1: Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.
−6: Create a white Avatar creature token. It has "This creature's power and toughness are each equal to your life total."

Ajani, the Greathearted

Creatures you control have vigilance.
+1: You gain 3 life.
−2: Put a +1/+1 counter on each creature you control and a loyalty counter on each other planeswalker you control.

Tribute to the World Tree

Whenever a creature you control enters, draw a card if its power is 3 or greater. Otherwise, put two +1/+1 counters on it.

Jiang Yanggu, Wildcrafter

Each creature you control with a +1/+1 counter on it has "{T}: Add one mana of any color."
−1: Put a +1/+1 counter on target creature.

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

Ozolith, the Shattered Spire

If one or more +1/+1 counters would be put on an artifact or creature you control, that many plus one +1/+1 counters are put on it instead.
{1}{G}, {T}: Put a +1/+1 counter on target artifact or creature you control. Activate only as a sorcery.
Cycling {2} ({2}, Discard this card: Draw a card.)