Akoum Battlesinger

Haste
Whenever Akoum Battlesinger or another Ally you control enters, you may have Ally creatures you control get +1/+0 until end of turn.

Mountain

Rally the Righteous

Radiance — Untap target creature and each other creature that shares a color with it. Those creatures get +2/+0 until end of turn.

Martial Glory

Target creature gets +3/+0 until end of turn.
Target creature gets +0/+3 until end of turn.

Angelfire Ignition

Put two +1/+1 counters on target creature. It gains vigilance, trample, lifelink, indestructible, and haste until end of turn.
Flashback {2}{R}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

War Flare

Creatures you control get +2/+1 until end of turn. Untap those creatures.

Agrus Kos, Wojek Veteran

Whenever Agrus Kos, Wojek Veteran attacks, attacking red creatures get +2/+0 and attacking white creatures get +0/+2 until end of turn.

Adriana, Captain of the Guard

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Other creatures you control have melee. (If a creature has multiple instances of melee, each triggers separately.)

Plains

Squee's Embrace

Enchant creature
Enchanted creature gets +2/+2.
When enchanted creature dies, return that card to its owner's hand.

Cerodon Yearling

Anointer of Champions

{T}: Target attacking creature gets +1/+1 until end of turn.

Ambush Paratrooper

Flash
Flying
{5}: Creatures you control get +1/+1 until end of turn.

Angelic Captain

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