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.

Tajuru Warcaller

Rally — Whenever Tajuru Warcaller or another Ally you control enters, creatures you control get +2/+2 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.

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.

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.

Zulaport Cutthroat

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.

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.

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}

Drana, Liberator of Malakir

Flying, first strike
Whenever Drana, Liberator of Malakir deals combat damage to a player, put a +1/+1 counter on each attacking creature you control.

Harabaz Druid

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

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.

Munda's Vanguard

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

Rhythm of the Wild

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

Kazuul Warlord

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

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.

Seascape Aerialist

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

Makindi Patrol

Rally — Whenever Makindi Patrol or another Ally you control enters, creatures you control gain vigilance until end of turn.

Sea Gate Loremaster

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

Lantern Scout

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

Herald's Horn

As Herald's Horn 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.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

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.

Resolute Blademaster

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

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.

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.

Tajuru Archer

Whenever Tajuru Archer or another Ally you control enters, you may have Tajuru Archer deal damage to target creature with flying equal to the number of Allies you control.

Kor Bladewhirl

Rally — Whenever Kor Bladewhirl or another Ally you control enters, creatures you control gain first strike until end of turn.

Urza's Incubator

As Urza's Incubator enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

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.

Kalastria Healer

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

Ondu Champion

Rally — Whenever Ondu Champion or another Ally you control enters, creatures you control gain trample until end of turn.

Door of Destinies

As Door of Destinies enters, 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.

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.

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker 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.

Etchings of the Chosen

As Etchings of the Chosen enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{1}, Sacrifice a creature of the chosen type: Target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

And They Shall Know No Fear

Choose a creature type. Creatures you control of the chosen type get +1/+0 and gain indestructible until end of turn.

Vanquisher's Banner

As Vanquisher's Banner 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.

Legion Loyalty

Creatures you control have myriad. (Whenever a creature with myriad attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

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.

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)