Island

Harbin, Vanguard Aviator

Flying
Whenever you attack with five or more Soldiers, creatures you control get +1/+1 and gain flying until end of turn.

Plains

Fortified Beachhead

As Fortified Beachhead enters, you may reveal a Soldier card from your hand. Fortified Beachhead enters tapped unless you revealed a Soldier card this way or you control a Soldier.
{T}: Add {W} or {U}.
{5}, {T}: Soldiers you control get +1/+1 until end of turn.

Runic Shot

Kicker {U} (You may pay an additional {U} as you cast this spell.)
Destroy target tapped creature. If this spell was kicked, scry 2.

Ambush Paratrooper

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

Rescue Retriever

Flash
When Rescue Retriever enters, put a +1/+1 counter on each other Soldier you control.
Prevent all damage that would be dealt to other attacking Soldiers you control.

Air Marshal

{3}: Target Soldier gains flying until end of turn.

Resolute Reinforcements

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, create a 1/1 white Soldier creature token.

Aeronaut Cavalry

Flying
When Aeronaut Cavalry enters, put a +1/+1 counter on another target Soldier you control.

Yotian Tactician

Siege Veteran

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.
Whenever another nontoken Soldier you control dies, create a 1/1 colorless Soldier artifact creature token.

Valiant Veteran

Other Soldiers you control get +1/+1.
{3}{W}{W}, Exile Valiant Veteran from your graveyard: Put a +1/+1 counter on each Soldier you control.