Maybe

Congregate

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

Thoughtweft Charge

Target creature gets +3/+3 until end of turn. If a creature entered the battlefield under your control this turn, draw a card.

Arcane Signet

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

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.)

Strength of the Coalition

Kicker {2}{W} (You may pay an additional {2}{W} as you cast this spell.)
Target creature you control gets +2/+2 until end of turn. If this spell was kicked, put a +1/+1 counter on each creature you control.

Canopy Vista

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

Don't Have

Pearl Medallion

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

Kaheera, the Orphanguard

Companion — Each creature card in your starting deck is a Cat, Elemental, Nightmare, Dinosaur, or Beast card. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Vigilance
Each other creature you control that's a Cat, Elemental, Nightmare, Dinosaur, or Beast gets +1/+1 and has vigilance.

Primal Vigor

If one or more tokens would be created, twice that many of those tokens are created instead.
If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Cut a Deal

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

Brimaz, King of Oreskos

Vigilance
Whenever Brimaz attacks, create a 1/1 white Cat Soldier creature token with vigilance that's attacking.
Whenever Brimaz blocks a creature, create a 1/1 white Cat Soldier creature token with vigilance that's blocking that creature.

Glittering Lion

Prevent all damage that would be dealt to this creature.
{3}: Until end of turn, this creature loses "Prevent all damage that would be dealt to this creature." Any player may activate this ability.

King of the Pride

Glorious Sunrise

At the beginning of combat on your turn, choose one —
• Creatures you control get +1/+1 and gain trample until end of turn.
• Target land gains "{T}: Add {G}{G}{G}" until end of turn.
• Draw a card if you control a creature with power 3 or greater.
• You gain 3 life.

Jewel Thief

Vigilance, trample
When this creature enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Overgrown Farmland

This land enters tapped unless you control two or more other lands.
{T}: Add {G} or {W}.

Kutzil, Malamet Exemplar

Your opponents can't cast spells during your turn.
Whenever one or more creatures you control each with power greater than its base power deals combat damage to a player, draw a card.

Colossification

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature gets +20/+20.

Felidar Retreat

Landfall — Whenever a land you control enters, choose one —
• Create a 2/2 white Cat Beast creature token.
• Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.

Anointed Procession

White Sun's Zenith

Create X 2/2 white Cat creature tokens. Shuffle White Sun's Zenith into its owner's library.

Ajani, Caller of the Pride

+1: Put a +1/+1 counter on up to one target creature.
−3: Target creature gains flying and double strike until end of turn.
−8: Create X 2/2 white Cat creature tokens, where X is your life total.

Trouble in Pairs

If an opponent would begin an extra turn, that player skips that turn instead.
Whenever an opponent attacks you with two or more creatures, draws their second card each turn, or casts their second spell each turn, you draw a card.

Herd Heirloom

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.
{T}: Until end of turn, target creature you control with power 4 or greater gains trample and "Whenever this creature deals combat damage to a player, draw a card."

Basri's Solidarity

Put a +1/+1 counter on each creature you control.

Untamed Wilds

Search your library for a basic land card, put that card onto the battlefield, then shuffle.

Pride Sovereign

This creature gets +1/+1 for each other Cat you control.
{W}, {T}, Exert this creature: Create two 1/1 white Cat creature tokens with lifelink. (An exerted creature won't untap during your next untap step.)

Prava of the Steel Legion

During your turn, creature tokens you control get +1/+4.
{3}{W}: Create a 1/1 white Soldier creature token.
Partner (You can have two commanders if both have partner.)

Invigorating Surge

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on that creature.

Mutable Explorer

Changeling (This card is every creature type.)
When this creature enters, create a tapped Mutavault token. (It's a land with "{T}: Add {C}" and "{1}: This token becomes a 2/2 creature with all creature types until end of turn. It's still a land.")

Wilderness Reclamation

At the beginning of your end step, untap all lands you control.

Ajani, Strength of the Pride

+1: You gain life equal to the number of creatures you control plus the number of planeswalkers you control.
−2: Create a 2/2 white Cat Soldier creature token named Ajani's Pridemate with "Whenever you gain life, put a +1/+1 counter on this token."
0: If you have at least 15 life more than your starting life total, exile Ajani and each artifact and creature your opponents control.

Revitalize

Cat Collector

When this creature enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Whenever you gain life for the first time during each of your turns, create a 1/1 white Cat creature token.

Defiant Strike

Target creature gets +1/+0 until end of turn.
Draw a card.

Animal Sanctuary

{T}: Add {C}.
{2}, {T}: Put a +1/+1 counter on target Bird, Cat, Dog, Goat, Ox, or Snake.

Helpful Hunter

Glittering Lynx

Prevent all damage that would be dealt to this creature.
{2}: Until end of turn, this creature loses "Prevent all damage that would be dealt to this creature." Any player may activate this ability.

Flock Impostor

Changeling (This card is every creature type.)
Flash
Flying
When this creature enters, return up to one other target creature you control to its owner's hand.

Pridemalkin

When this creature enters, put a +1/+1 counter on target creature you control.
Each creature you control with a +1/+1 counter on it has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Shimmerwilds Growth

Enchant land
As this Aura enters, choose a color.
Enchanted land is the chosen color.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of the chosen color.

Gavony Township

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

Sol Ring

Fellwar Stone

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

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Secluded Steppe

This land enters tapped.
{T}: Add {W}.
Cycling {W} ({W}, Discard this card: Draw a card.)

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Arahbo, the First Fang

Other Cats you control get +1/+1.
Whenever Arahbo or another nontoken Cat you control enters, create a 1/1 white Cat creature token.

Wary Thespian

When this creature enters or dies, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Path of Ancestry

This land 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.)

Generous Gift

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

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Claws Out

Affinity for Cats (This spell costs {1} less to cast for each Cat you control.)
Creatures you control get +2/+2 until end of turn.

Monstrous Growth

Target creature gets +4/+4 until end of turn.

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.

Glorious Anthem

Prideful Parent

Vigilance (Attacking doesn't cause this creature to tap.)
When this creature enters, create a 1/1 white Cat creature token.

Basri's Acolyte

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
When this creature enters, put a +1/+1 counter on each of up to two other target creatures you control.

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}.

Clever Concealment

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Any number of target nonland permanents you control phase out. (Treat them and anything attached to them as though they don't exist until your next turn.)

Elspeth, Storm Slayer

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
+1: Create a 1/1 white Soldier creature token.
0: Put a +1/+1 counter on each creature you control. Those creatures gain flying until your next turn.
−3: Destroy target creature an opponent controls with mana value 3 or greater.

Plains

Intangible Virtue

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

Migration Path

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swift Response

Feline Sovereign

Other Cats you control get +1/+1 and have protection from Dogs.
Whenever one or more Cats you control deal combat damage to a player, destroy up to one target artifact or enchantment that player controls.

Lionheart Glimmer

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever you attack, creatures you control get +1/+1 until end of turn.

Canopy Stalker

This creature must be blocked if able.
When this creature dies, you gain 1 life for each creature that died this turn.

Selesnya Signet

Basri, Tomorrow's Champion

{W}, {T}, Exert Basri: Create a 1/1 white Cat creature token with lifelink. (An exerted creature won't untap during your next untap step.)
Cycling {2}{W} ({2}{W}, Discard this card: Draw a card.)
When you cycle this card, Cats you control gain hexproof and indestructible until end of turn.

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.)

Cubwarden

Mutate {2}{W}{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.)
Lifelink
Whenever this creature mutates, create two 1/1 white Cat creature tokens with lifelink.

Blossoming Sands

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {G} or {W}.

Blossoming Defense

Target creature you control gets +2/+2 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Radiant Grove

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

Sunpetal Grove

This land enters tapped unless you control a Forest or a Plains.
{T}: Add {G} or {W}.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Swords to Plowshares

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

Mirrormind Crown

As long as this Equipment is attached to a creature, the first time you would create one or more tokens each turn, you may instead create that many tokens that are copies of equipped creature.
Equip {2}

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Forest

Gathering Stone

As this artifact enters, choose a creature type.
Spells you cast of the chosen type cost {1} less to cast.
When this artifact enters and at the beginning of your upkeep, look at the top card of your library. If it's a card of the chosen type, you may reveal it and put it into your hand. If you don't put the card into your hand, you may put it into your graveyard.

Stalking Leonin

When this creature enters, secretly choose an opponent.
Reveal the player you chose: Exile target creature that's attacking you if it's controlled by the chosen player. Activate only once.

Whitemane Lion

Flash
When this creature enters, return a creature you control to its owner's hand.

Command Tower

Hungry Lynx

Cats you control have protection from Rats. (They can't be blocked, targeted, or dealt damage by Rats.)
At the beginning of your end step, target opponent creates a 1/1 black Rat creature token with deathtouch.
Whenever a Rat dies, put a +1/+1 counter on each Cat you control.

Urza's Incubator

As this artifact enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.