Rin and Seri, Inseparable

Whenever you cast a Dog spell, create a 1/1 green Cat creature token.
Whenever you cast a Cat spell, create a 1/1 white Dog creature token.
{R}{G}{W}, {T}: Rin and Seri deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.

Forest

Frondland Felidar

Vigilance
Creatures you control with vigilance have "{1}, {T}: Tap target creature."

Arni Slays the Troll

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Target creature you control fights up to one target creature you don't control.
II — Add {R}. Put two +1/+1 counters on up to one target creature you control.
III — You gain life equal to the greatest power among creatures you control.

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.

Gods' Hall Guardian

Vigilance
Foretell {3}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Oath of Ajani

When Oath of Ajani enters, put a +1/+1 counter on each creature you control.
Planeswalker spells you cast cost {1} less to cast.

Alpine Watchdog

Vigilance (Attacking doesn't cause this creature to tap.)

Ajani's Sunstriker

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

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.

Armory of Iroas

Whenever equipped creature attacks, put a +1/+1 counter on it.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

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."

Leonin of the Lost Pride

When this creature dies, exile target card from an opponent's graveyard.

Titanic Ultimatum

Until end of turn, creatures you control get +5/+5 and gain first strike, trample, and lifelink.

Bolt Hound

Haste (This creature can attack and {T} as soon as it comes under your control.)
Whenever this creature attacks, other creatures you control get +1/+0 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.

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Titanic Growth

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

Hero of the Pride

Whenever you cast a spell that targets this creature, creatures you control get +1/+0 until end of turn.

Sigil of the Nayan Gods

Enchant creature
Enchanted creature gets +1/+1 for each creature you control.
Cycling {G/W} ({G/W}, Discard this card: Draw a card.)

Lukka, Wayward Bonder

+1: You may discard a card. If you do, draw a card. If a creature card was discarded this way, draw two cards instead.
−2: Return target creature card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of your next upkeep.
−7: You get an emblem with "Whenever a creature you control enters, it deals damage equal to its power to any target."

Mila, Crafty Companion

Whenever an opponent attacks one or more planeswalkers you control, put a loyalty counter on each planeswalker you control.
Whenever a permanent you control becomes the target of a spell or ability an opponent controls, you may draw a card.

Mila, Crafty Companion // Lukka, Wayward Bonder

Ajani, Adversary of Tyrants

+1: Put a +1/+1 counter on each of up to two target creatures.
−2: Return target creature card with mana value 2 or less from your graveyard to the battlefield.
−7: You get an emblem with "At the beginning of your end step, create three 1/1 white Cat creature tokens with lifelink."

Bayou Groff

As an additional cost to cast this spell, sacrifice a creature or pay {3}.

Territorial Scythecat

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Landfall — Whenever a land you control enters, put a +1/+1 counter on this creature.

Jungle Shrine

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

Ajani's Chosen

Whenever an enchantment you control enters, create a 2/2 white Cat creature token. If that enchantment is an Aura, you may attach it to the token.

Keeper of Fables

Whenever one or more non-Human creatures you control deal combat damage to a player, draw a card.

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.

Adamant Will

Target creature gets +2/+2 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Resounding Roar

Target creature gets +3/+3 until end of turn.
Cycling {5}{R}{G}{W} ({5}{R}{G}{W}, Discard this card: Draw a card.)
When you cycle this card, target creature gets +6/+6 until end of turn.

Armadillo Cloak

Enchant creature
Enchanted creature gets +2/+2 and has trample.
Whenever enchanted creature deals damage, you gain that much life.

Obelisk of Naya

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.

Simple

Pure

Pure // Simple

Jedit Ojanen of Efrava

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
Whenever Jedit Ojanen attacks or blocks, create a 2/2 green Cat Warrior creature token with forestwalk.

Ajani's Last Stand

Whenever a creature or planeswalker you control dies, you may sacrifice this enchantment. If you do, create a 4/4 white Avatar creature token with flying.
When a spell or ability an opponent controls causes you to discard this card, if you control a Plains, create a 4/4 white Avatar creature token with flying.

Arcbound Slasher

Modular 4 (This creature enters 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 with your choice of an additional +1/+1 counter or haste.)

Isamaru, Hound of Konda

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.)

Igneous Cur

{1}{R}: This creature gets +2/+0 until end of turn.

Sovereign Okinec Ahau

Ward {2}
Whenever Sovereign Okinec Ahau attacks, for each creature you control with power greater than that creature's base power, put a number of +1/+1 counters on that creature equal to the difference.

Marisi, Breaker of the Coil

Your opponents can't cast spells during combat.
Whenever a creature you control deals combat damage to a player, goad each creature that player controls. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

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.

Arcbound Mouser

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

Door of Destinies

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

Naya Charm

Choose one —
• Naya Charm deals 3 damage to target creature.
• Return target card from a graveyard to its owner's hand.
• Tap all creatures target player controls.

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.

Mayael's Aria

At the beginning of your upkeep, put a +1/+1 counter on each creature you control if you control a creature with power 5 or greater. Then you gain 10 life if you control a creature with power 10 or greater. Then you win the game if you control a creature with power 20 or greater.

Ancient Grudge

Destroy target artifact.
Flashback {G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Bronzehide Lion

{G}{W}: This creature gains indestructible until end of turn.
When this creature dies, return it to the battlefield. It's an Aura enchantment with enchant creature you control and "{G}{W}: Enchanted creature gains indestructible until end of turn," and it loses all other abilities.

Jetmir's Garden

({T}: Add {R}, {G}, or {W}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on this creature.

Ajani's Presence

Strive — This spell costs {2}{W} more to cast for each target beyond the first.
Any number of target creatures each get +1/+1 and gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Selfless Savior

Sacrifice this creature: Another target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Pack Leader

Other Dogs you control get +1/+1.
Whenever this creature attacks, prevent all combat damage that would be dealt this turn to Dogs you control.

Arcbound Tracker

Menace
Modular 2 (This creature enters with two +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Whenever you cast a spell other than your first spell each turn, put a +1/+1 counter on this creature.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Plains

Sabertooth Mauler

At the beginning of your end step, if a creature died this turn, put a +1/+1 counter on this creature and untap it.

Regal Caracal

Other Cats you control get +1/+1 and have lifelink. (Damage dealt by those creatures also causes you to gain that much life.)
When this creature enters, create two 1/1 white Cat creature tokens with lifelink.

Ajani, Valiant Protector

+2: Put two +1/+1 counters on up to one target creature.
+1: Reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.
−11: Put X +1/+1 counters on target creature, where X is your life total. That creature gains trample until end of turn.

Mountain

Fiery Justice

Fiery Justice deals 5 damage divided as you choose among any number of targets. Target opponent gains 5 life.

Akoum Hellhound

Landfall — Whenever a land you control enters, this creature gets +2/+2 until end of turn.

Blossoming Sands

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

Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Kazandu Refuge

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

Cradle of Vitality

Whenever you gain life, you may pay {1}{W}. If you do, put a +1/+1 counter on target creature for each 1 life you gained.

Chandra's Magmutt

{T}: This creature deals 1 damage to target player or planeswalker.

Prowling Felidar

Vigilance
Landfall — Whenever a land you control enters, put a +1/+1 counter on this creature.

Abiding Grace

At the beginning of your end step, choose one —
• You gain 1 life.
• Return target creature card with mana value 1 from your graveyard to the battlefield.

Command Tower

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

Arcbound Shikari

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

Gruul Turf

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {R}{G}.

Ajani's Influence

Put two +1/+1 counters on target creature.
Look at the top five cards of your library. You may reveal a white card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Animal Sanctuary

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

Rambunctious Mutt

When this creature enters, destroy target artifact or enchantment an opponent controls.