Crown of Ascension

Enchant creature
Enchanted creature has flying.
Sacrifice Crown of Ascension: Enchanted creature and other creatures that share a creature type with it gain flying until end of turn.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Universal Automaton

Changeling (This card is every creature type.)

Tajuru Beastmaster

Rally — Whenever Tajuru Beastmaster or another Ally you control enters, creatures you control get +1/+1 until end of turn.

Mountain

Oran-Rief Survivalist

Whenever Oran-Rief Survivalist or another Ally you control enters, you may put a +1/+1 counter on Oran-Rief Survivalist.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

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.

Forest

Graypelt Hunter

Trample
Whenever Graypelt Hunter or another Ally you control enters, you may put a +1/+1 counter on Graypelt Hunter.

Blur

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Umara Raptor

Flying
Whenever Umara Raptor or another Ally you control enters, you may put a +1/+1 counter on Umara Raptor.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Ondu Champion

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

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Island

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.