Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters the battlefield, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.

Frenzied Arynx

Riot (This creature enters the battlefield with your choice of a +1/+1 counter or haste.)
Trample
{4}{R}{G}: Frenzied Arynx gets +3/+0 until end of turn.

Seaside Citadel

Seaside Citadel enters the battlefield tapped.
{T}: Add {G}, {W}, or {U}.

Streetwise Negotiator

Backup 1 (When this creature enters the battlefield, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
This creature assigns combat damage equal to its toughness rather than its power.

Crazed Firecat

When Crazed Firecat enters the battlefield, flip a coin until you lose a flip. Put a +1/+1 counter on Crazed Firecat for each flip you won.

Kodama's Reach

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.

Fellwar Stone

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

Pride Sovereign

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

Arcbound Shikari

First strike
When Arcbound Shikari enters the battlefield, put a +1/+1 counter on each other artifact creature you control.
Modular 2 (This creature enters the battlefield with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Vanquisher's Banner

As Vanquisher's Banner enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

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.

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.

Evolving Wilds

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

Arcbound Slasher

Modular 4 (This creature enters the battlefield with four +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Riot (This creature enters the battlefield with your choice of an additional +1/+1 counter or haste.)

Kindred Discovery

As Kindred Discovery enters the battlefield, choose a creature type.
Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.

Command Tower

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

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Bola Slinger

Backup 1 (When this creature enters the battlefield, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Whenever this creature attacks, tap target artifact or creature an opponent controls.

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter the battlefield with your choice of a +1/+1 counter or haste.)

Island

Mystic Monastery

Mystic Monastery enters the battlefield tapped.
{T}: Add {U}, {R}, or {W}.

Reflections of Littjara

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Fleecemane Lion

{3}{G}{W}: Monstrosity 1. (If this creature isn't monstrous, put a +1/+1 counter on it and it becomes monstrous.)
As long as Fleecemane Lion is monstrous, it has hexproof and indestructible.

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Arcane Signet

Counterspell

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Adorned Pouncer

Double strike
Eternalize {3}{W}{W} ({3}{W}{W}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Cat with no mana cost. Eternalize only as a sorcery.)

Basri's Acolyte

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

Path of Ancestry

Path of Ancestry enters the battlefield 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.)

Wary Thespian

When Wary Thespian enters the battlefield or dies, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Chromatic Orrery

You may spend mana as though it were mana of any color.
{T}: Add {C}{C}{C}{C}{C}.
{5}, {T}: Draw a card for each color among permanents you control.

Chrome Prowler

Flash
When Chrome Prowler enters the battlefield, tap target creature an opponent controls.

Arcbound Mouser

Lifelink
Modular 1 (This creature enters the battlefield with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Frontier Bivouac

Frontier Bivouac enters the battlefield tapped.
{T}: Add {G}, {U}, or {R}.

Exotic Orchard

Dreadmalkin

Menace (This creature can't be blocked except by two or more creatures.)
{2}{B}, Sacrifice another creature or planeswalker: Put two +1/+1 counters on Dreadmalkin.

Door of Destinies

As Door of Destinies enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Nature's Lore

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

Stonework Puma

Mountain

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Secluded Courtyard

As Secluded Courtyard enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Swamp

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.

Cultivate

Sol Ring

Jungle Shrine

Jungle Shrine enters the battlefield tapped.
{T}: Add {R}, {G}, or {W}.

Herald's Horn

As Herald's Horn enters the battlefield, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

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.

Rampant Growth

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

Unclaimed Territory

As Unclaimed Territory enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Heroic Intervention

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

Forest

Plains

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Lion Sash

{W}: Exile target card from a graveyard. If it was a permanent card, put a +1/+1 counter on Lion Sash.
Equipped creature gets +1/+1 for each +1/+1 counter on Lion Sash.
Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Thirsting Roots

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Wasitora, Nekoru Queen

Flying, trample
Whenever Wasitora, Nekoru Queen deals combat damage to a player, that player sacrifices a creature. If the player can't, you create a 3/3 black, red, and green Cat Dragon creature token with flying.

Scrounging Bandar

Scrounging Bandar enters the battlefield with two +1/+1 counters on it.
At the beginning of your upkeep, you may move any number of +1/+1 counters from Scrounging Bandar onto another target creature.

Denry Klin, Editor in Chief

Denry Klin, Editor in Chief enters the battlefield with your choice of a +1/+1, first strike, or vigilance counter on it.
Whenever a nontoken creature enters the battlefield under your control, if Denry has counters on it, put the same number of each kind of counter on that creature.

Pridemalkin

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

Terramorphic Expanse

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

Zar Ojanen, Scion of Efrava

Domain — Whenever Zar Ojanen, Scion of Efrava becomes tapped, put a +1/+1 counter on each creature you control with toughness less than the number of basic land types among lands you control.

Jetmir's Fixer

{R}{G}: Jetmir's Fixer gets +1/+1 until end of turn. If mana from a Treasure was spent to activate this ability, put a +1/+1 counter on Jetmir's Fixer instead.

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.

Regal Caracal

Other Cats you control get +1/+1 and have lifelink.
When Regal Caracal enters the battlefield, create two 1/1 white Cat creature tokens with lifelink.