Thoughtweft Trio

First strike, vigilance
Champion a Kithkin (When this enters, sacrifice it unless you exile another Kithkin you control. When this leaves the battlefield, that card returns to the battlefield.)
This creature can block any number of creatures.

Spara's Headquarters

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

Radiant Destiny

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
As this enchantment enters, choose a creature type.
Creatures you control of the chosen type get +1/+1. As long as you have the city's blessing, they also have vigilance.

Cathars' Crusade

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

Thoughtweft Gambit

Tap all creatures your opponents control and untap all creatures you control.

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.

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Thistledown Liege

Flash
Other white creatures you control get +1/+1.
Other blue creatures you control get +1/+1.

Cloudgoat Ranger

When this creature enters, create three 1/1 white Kithkin Soldier creature tokens.
Tap three untapped Kithkin you control: This creature gets +2/+0 and gains flying until end of turn.

Sol Ring

Augury Adept

Whenever this creature deals combat damage to a player, reveal the top card of your library and put that card into your hand. You gain life equal to its mana value.

Forest

Ballyrush Banneret

Kithkin spells and Soldier spells you cast cost {1} less to cast.

Swords to Plowshares

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

Springjack Shepherd

Chroma — When this creature enters, create a 0/1 white Goat creature token for each white mana symbol in the mana costs of permanents you control.

Azorius Signet

Kinsbaile Borderguard

This creature enters with a +1/+1 counter on it for each other Kithkin you control.
When this creature dies, create a 1/1 white Kithkin Soldier creature token for each counter on it.

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.

Order of Whiteclay

{1}{W}{W}, {Q}: Return target creature card with mana value 3 or less from your graveyard to the battlefield. ({Q} is the untap symbol.)

Chulane, Teller of Tales

Vigilance
Whenever you cast a creature spell, draw a card, then you may put a land card from your hand onto the battlefield.
{3}, {T}: Return target creature you control to its owner's hand.

Command Tower

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

Ballynock Cohort

First strike
This creature gets +1/+1 as long as you control another white creature.

Vanquisher's Banner

As this artifact enters, 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.

Galepowder Mage

Flying
Whenever this creature attacks, exile another target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Arcane Signet

Goldmeadow Stalwart

As an additional cost to cast this spell, reveal a Kithkin card from your hand or pay {3}.

Prairie Stream

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

Breeding Pool

({T}: Add {G} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Steel of the Godhead

Enchant creature
As long as enchanted creature is white, it gets +1/+1 and has lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)
As long as enchanted creature is blue, it gets +1/+1 and can't be blocked.

Amrou Kithkin

This creature can't be blocked by creatures with power 3 or greater.

Ballynock Trapper

{T}: Tap target creature.
Whenever you cast a white spell, you may untap this creature.

Rampant Growth

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

Kindred Summons

Choose a creature type. Reveal cards from the top of your library until you reveal X creature cards of the chosen type, where X is the number of creatures you control of that type. Put those cards onto the battlefield, then shuffle the rest of the revealed cards into your library.

Kinsbaile Courier

When this creature enters, put a +1/+1 counter on target creature.
Encore {2}{W} ({2}{W}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Preeminent Captain

First strike (This creature deals combat damage before creatures without first strike.)
Whenever this creature attacks, you may put a Soldier creature card from your hand onto the battlefield tapped and attacking.

Surge of Thoughtweft

Creatures you control get +1/+1 until end of turn. If you control a Kithkin, draw a card.

Plains

Crib Swap

Changeling (This card is every creature type.)
Exile target creature. Its controller creates a 1/1 colorless Shapeshifter creature token with changeling.

Kithkin Mourncaller

Whenever an attacking Kithkin or Elf is put into your graveyard from the battlefield, you may draw a card.

Temple Garden

({T}: Add {G} or {W}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Island

Wizened Cenn

Other Kithkin creatures you control get +1/+1.

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.

Canopy Vista

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

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.

Kithkin Daggerdare

{G}, {T}: Target attacking creature gets +2/+2 until end of turn.

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Seaside Citadel

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

Zealous Guardian

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.

Mirrorweave

Each other creature becomes a copy of target nonlegendary creature until end of turn.

Kithkin Zephyrnaut

Kinship — At the beginning of your upkeep, you may look at the top card of your library. If it shares a creature type with this creature, you may reveal it. If you do, this creature gets +2/+2 and gains flying and vigilance until end of turn.

Ascend from Avernus

Return all creature and planeswalker cards with mana value X or less from your graveyard to the battlefield. Exile Ascend from Avernus.

Order of the Golden Cricket

Whenever this creature attacks, you may pay {W}. If you do, it gains flying until end of turn.

Realmwalker

Changeling (This card is every creature type.)
As this creature enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Mistmeadow Witch

{2}{W}{U}: Exile target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Cultivate

Mistmeadow Skulk

Lifelink, protection from mana value 3 or greater

Sea of Clouds

This land enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Farseek

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

Obelisk of Urd

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.)
As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Overgrown Farmland

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

Repel Intruders

Create two 1/1 white Kithkin Soldier creature tokens if {W} was spent to cast this spell. Counter up to one target creature spell if {U} was spent to cast this spell. (Do both if {W}{U} was spent.)

Gaddock Teeg

Noncreature spells with mana value 4 or greater can't be cast.
Noncreature spells with {X} in their mana costs can't be cast.

Selesnya Signet

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on this enchantment.
As long as this enchantment has seven or more quest counters on it, creatures you control get +5/+5.

Kithkin Billyrider

Knight of Meadowgrain

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

Brigid, Hero of Kinsbaile

First strike
{T}: Brigid deals 2 damage to each attacking or blocking creature target player controls.

Cenn's Tactician

{W}, {T}: Put a +1/+1 counter on target Soldier creature.
Each creature you control with a +1/+1 counter on it can block an additional creature each combat.

Reflections of Littjara

As this enchantment enters, 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.)

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Cenn's Heir

Whenever this creature attacks, it gets +1/+1 until end of turn for each other attacking Kithkin.

Goldmeadow Harrier

Herald's Horn

As this artifact enters, 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.

Gavony Township

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

Militia's Pride

Whenever a nontoken creature you control attacks, you may pay {W}. If you do, create a 1/1 white Kithkin Soldier creature token that's tapped and attacking.

Hallowed Fountain

({T}: Add {W} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Kithkin Rabble

Vigilance
Kithkin Rabble's power and toughness are each equal to the number of white permanents you control.

Kithkin Harbinger

When this creature enters, you may search your library for a Kithkin card, reveal it, then shuffle and put that card on top.

Deserted Beach

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

Patrol Signaler

{1}{W}, {Q}: Create a 1/1 white Kithkin Soldier creature token. ({Q} is the untap symbol.)