Harsh Mercy

Each player chooses a creature type. Destroy all creatures that aren't of a type chosen this way. They can't be regenerated.

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on Soulherder.
At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Jwari Shapeshifter

You may have Jwari Shapeshifter enter as a copy of any Ally creature on the battlefield.

Hero of Goma Fada

Rally — Whenever Hero of Goma Fada or another Ally you control enters, creatures you control gain indestructible until end of turn.

Beastcaller Savant

Haste
{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Bala Ged Thief

Whenever Bala Ged Thief or another Ally you control enters, target player reveals a number of cards from their hand equal to the number of Allies you control. You choose one of them. That player discards that card.

Murasa Pyromancer

Whenever Murasa Pyromancer or another Ally you control enters, you may have Murasa Pyromancer deal damage to target creature equal to the number of Allies you control.

Selesnya Signet

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

Sea Gate Loremaster

{T}: Draw a card for each Ally you control.

Progenitor Mimic

You may have Progenitor Mimic enter as a copy of any creature on the battlefield, except it has "At the beginning of your upkeep, if this creature isn't a token, create a token that's a copy of this creature."

Angelic Captain

Flying
Whenever Angelic Captain attacks, it gets +1/+1 until end of turn for each other attacking Ally.

Tuktuk Scrapper

Whenever Tuktuk Scrapper or another Ally you control enters, you may destroy target artifact. If that artifact is put into a graveyard this way, Tuktuk Scrapper deals damage to that artifact's controller equal to the number of Allies you control.

Molten Echoes

As Molten Echoes enters, choose a creature type.
Whenever a nontoken creature you control of the chosen type enters, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Mirror Image

You may have Mirror Image enter as a copy of a creature you control.

Malakir Soothsayer

Cohort — {T}, Tap an untapped Ally you control: You draw a card and you lose 1 life.

Unified Front

Converge — Create a 1/1 white Kor Ally creature token for each color of mana spent to cast this spell.

Lantern Scout

Rally — Whenever Lantern Scout or another Ally you control enters, creatures you control gain lifelink until end of turn.

Munda, Ambush Leader

Haste
Rally — Whenever Munda, Ambush Leader or another Ally you control enters, you may look at the top four cards of your library. If you do, reveal any number of Ally cards from among them, then put those cards on top of your library in any order and the rest on the bottom in any order.

Allied Reinforcements

Create two 2/2 white Knight Ally creature tokens.

General Tazri

When General Tazri enters, you may search your library for an Ally creature card, reveal it, put it into your hand, then shuffle.
{W}{U}{B}{R}{G}: Ally creatures you control get +X/+X until end of turn, where X is the number of colors among those creatures.

Oath of Gideon

When Oath of Gideon enters, create two 1/1 white Kor Ally creature tokens.
Each planeswalker you control enters with an additional loyalty counter on it.

Seascape Aerialist

Whenever Seascape Aerialist or another Ally you control enters, you may have Ally creatures you control gain flying until end of turn.

Talus Paladin

Whenever Talus Paladin or another Ally you control enters, you may have Allies you control gain lifelink until end of turn, and you may put a +1/+1 counter on Talus Paladin.

Momentary Blink

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Mina and Denn, Wildborn

You may play an additional land on each of your turns.
{R}{G}, Return a land you control to its owner's hand: Target creature gains trample until end of turn.

Captain's Claws

Equipped creature gets +1/+0.
Whenever equipped creature attacks, create a 1/1 white Kor Ally creature token that's tapped and attacking.
Equip {1}

Hagra Diabolist

Whenever Hagra Diabolist or another Ally you control enters, you may have target player lose life equal to the number of Allies you control.

Kazuul Warlord

Whenever Kazuul Warlord or another Ally you control enters, you may put a +1/+1 counter on each Ally creature you control.

Firemantle Mage

Rally — Whenever Firemantle Mage or another Ally you control enters, creatures you control gain menace until end of turn. (A creature with menace can't be blocked except by two or more creatures.)

Halimar Excavator

Whenever Halimar Excavator or another Ally you control enters, target player mills X cards, where X is the number of Allies you control.

Kabira Evangel

Whenever Kabira Evangel or another Ally you control enters, you may choose a color. If you do, Allies you control gain protection from the chosen color until end of turn.

Open the Gates

Search your library for a basic land card or Gate card, reveal it, put it into your hand, then shuffle.

Generous Gift

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

Munda's Vanguard

Cohort — {T}, Tap an untapped Ally you control: Put a +1/+1 counter on each creature you control.

Kalastria Healer

Rally — Whenever Kalastria Healer or another Ally you control enters, each opponent loses 1 life and you gain 1 life.

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.

Join the Ranks

Create two 1/1 white Soldier Ally creature tokens.

March from the Tomb

Return any number of target Ally creature cards with total mana value 8 or less from your graveyard to the battlefield.

Grow from the Ashes

Kicker {2} (You may pay an additional {2} as you cast this spell.)
Search your library for a basic land card, put it onto the battlefield, then shuffle. If this spell was kicked, instead search your library for two basic land cards, put them onto the battlefield, then shuffle.

Turntimber Ranger

Whenever Turntimber Ranger or another Ally you control enters, you may create a 2/2 green Wolf creature token. If you do, put a +1/+1 counter on Turntimber Ranger.

Harabaz Druid

{T}: Add X mana of any one color, where X is the number of Allies you control.

Boros Signet

Agadeem Occultist

{T}: Put target creature card from an opponent's graveyard onto the battlefield under your control if its mana value is less than or equal to the number of Allies you control.

Call to the Kindred

Enchant creature
At the beginning of your upkeep, you may look at the top five cards of your library. If you do, you may put a creature card that shares a creature type with enchanted creature from among them onto the battlefield, then you put the rest of those cards on the bottom of your library in any order.

Skyshroud Claim

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

Chasm Guide

Rally — Whenever Chasm Guide or another Ally you control enters, creatures you control gain haste until end of turn.

Simic Signet

Veteran Warleader

Veteran Warleader's power and toughness are each equal to the number of creatures you control.
Tap another untapped Ally you control: Veteran Warleader gains your choice of first strike, vigilance, or trample until end of turn.

Retreat to Emeria

Landfall — Whenever a land you control enters, choose one —
• Create a 1/1 white Kor Ally creature token.
• Creatures you control get +1/+1 until end of turn.

Ondu Cleric

Whenever Ondu Cleric or another Ally you control enters, you may gain life equal to the number of Allies you control.

Drana's Chosen

Cohort — {T}, Tap an untapped Ally you control: Create a tapped 2/2 black Zombie creature token.

Grovetender Druids

Rally — Whenever Grovetender Druids or another Ally you control enters, you may pay {1}. If you do, create a 1/1 green Plant creature token.

Resolute Blademaster

Rally — Whenever Resolute Blademaster or another Ally you control enters, creatures you control gain double strike until end of turn.

Highland Berserker

Whenever Highland Berserker or another Ally you control enters, you may have Ally creatures you control gain first strike until end of turn.

Pillar of Origins

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