Haazda Marshal

Whenever Haazda Marshal and at least two other creatures attack, create a 1/1 white Soldier creature token with lifelink.

Mountain

Yotian Frontliner

Whenever Yotian Frontliner attacks, another target creature you control gets +1/+1 until end of turn.
Unearth {W} ({W}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Basri Ket Emblem

At the beginning of combat on your turn, create a 1/1 white Soldier creature token, then put a +1/+1 counter on each creature you control.

Plains

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Lightning Helix

Lightning Helix deals 3 damage to any target and you gain 3 life.

Boros Elite

Battalion — Whenever Boros Elite and at least two other creatures attack, Boros Elite gets +2/+2 until end of turn.

Basri Ket

+1: Put a +1/+1 counter on up to one target creature. It gains indestructible until end of turn.
−2: Whenever one or more nontoken creatures attack this turn, create that many 1/1 white Soldier creature tokens that are tapped and attacking.
−6: You get an emblem with "At the beginning of combat on your turn, create a 1/1 white Soldier creature token, then put a +1/+1 counter on each creature you control."

Firefist Striker

Battalion — Whenever Firefist Striker and at least two other creatures attack, target creature can't block this turn.

Soldier

Wind-Scarred Crag

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {R} or {W}.

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.

Wrenn's Resolve

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Firemane Avenger

Flying
Battalion — Whenever Firemane Avenger and at least two other creatures attack, Firemane Avenger deals 3 damage to any target and you gain 3 life.

Rugged Prairie

{T}: Add {C}.
{R/W}, {T}: Add {R}{R}, {R}{W}, or {W}{W}.

Assemble the Legion

At the beginning of your upkeep, put a muster counter on Assemble the Legion. Then create a 1/1 red and white Soldier creature token with haste for each muster counter on Assemble the Legion.

Captain of the Watch

Vigilance (Attacking doesn't cause this creature to tap.)
Other Soldier creatures you control get +1/+1 and have vigilance.
When Captain of the Watch enters, create three 1/1 white Soldier creature tokens.