Thoughtweft Lieutenant

Whenever this creature or another Kithkin you control enters, target creature you control gets +1/+1 and gains trample until end of turn.

Get Lost

Destroy target creature, enchantment, or planeswalker. Its controller creates two Map tokens. (They're artifacts with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")

Abandoned Air Temple

This land enters tapped unless you control a basic land.
{T}: Add {W}.
{3}{W}, {T}: Put a +1/+1 counter on each creature you control.

Seam Rip

When this enchantment enters, exile target nonland permanent an opponent controls with mana value 2 or less until this enchantment leaves the battlefield.

Temple Garden

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

Kinsbaile Aspirant

As an additional cost to cast this spell, behold a Kithkin or pay {2}. (To behold a Kithkin, choose a Kithkin you control or reveal a Kithkin card from your hand.)
Whenever another creature you control enters, this creature gets +1/+1 until end of turn.

Multiversal Passage

As this land enters, choose a basic land type. Then you may pay 2 life. If you don't, it enters tapped.
This land is the chosen type.

Figure of Fable

{G/W}: This creature becomes a Kithkin Scout with base power and toughness 2/3.
{1}{G/W}{G/W}: If this creature is a Scout, it becomes a Kithkin Soldier with base power and toughness 4/5.
{3}{G/W}{G/W}{G/W}: If this creature is a Soldier, it becomes a Kithkin Avatar with base power and toughness 7/8 and protection from each of your opponents.

Forest

Bristlebane Battler

Trample, ward {2}
This creature enters with five -1/-1 counters on it.
Whenever another creature you control enters while this creature has a -1/-1 counter on it, remove a -1/-1 counter from this creature.

Sheltered by Ghosts

Enchant creature you control
When this Aura enters, exile target nonland permanent an opponent controls until this Aura leaves the battlefield.
Enchanted creature gets +1/+0 and has lifelink and ward {2}.

Cavern of Souls

As this land enters, 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, and that spell can't be countered.

Hushwood Verge

{T}: Add {G}.
{T}: Add {W}. Activate only if you control a Forest or a Plains.

Case of the Gateway Express

When this Case enters, choose target creature you don't control. Each creature you control deals 1 damage to that creature.
To solve — Three or more creatures attacked this turn. (If unsolved, solve at the beginning of your end step.)
Solved — Creatures you control get +1/+0.

Ajani, Outland Chaperone

+1: Create a 1/1 green and white Kithkin creature token.
−2: Ajani deals 4 damage to target tapped creature.
−8: Look at the top X cards of your library, where X is your life total. You may put any number of nonland permanent cards with mana value 3 or less from among them onto the battlefield. Then shuffle.

Kinscaer Sentry

First strike, lifelink
Whenever this creature attacks, you may put a creature card with mana value X or less from your hand onto the battlefield tapped and attacking, where X is the number of attacking creatures you control.

Brigid, Doun's Mind

{T}: Add X {G} or X {W}, where X is the number of other creatures you control.
At the beginning of your first main phase, you may pay {W}. If you do, transform Brigid.

Brigid, Clachan's Heart

Whenever this creature enters or transforms into Brigid, Clachan's Heart, create a 1/1 green and white Kithkin creature token.
At the beginning of your first main phase, you may pay {G}. If you do, transform Brigid.