Frontline Medic

Battalion — Whenever Frontline Medic and at least two other creatures attack, creatures you control gain indestructible until end of turn.
Sacrifice Frontline Medic: Counter target spell with {X} in its mana cost unless its controller pays {3}.

Tajic, Blade of the Legion

Indestructible
Battalion — Whenever Tajic, Blade of the Legion and at least two other creatures attack, Tajic gets +5/+5 until end of turn.

Mountain

Justice Strike

Target creature deals damage to itself equal to its power.

Leonin Warleader

Whenever Leonin Warleader attacks, create two 1/1 white Cat creature tokens with lifelink that are tapped and attacking.

Aurelia, the Warleader

Flying, vigilance, haste
Whenever Aurelia, the Warleader attacks for the first time each turn, untap all creatures you control. After this phase, there is an additional combat phase.

Boros Elite

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

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.

Deafening Clarion

Choose one or both —
• Deafening Clarion deals 3 damage to each creature.
• Creatures you control gain lifelink until end of turn.

Haazda Marshal

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

Boros Garrison

Boros Garrison enters the battlefield tapped.
When Boros Garrison enters the battlefield, return a land you control to its owner's hand.
{T}: Add {R}{W}.

Makeshift Battalion

Battalion — Whenever Makeshift Battalion and at least two other creatures attack, put a +1/+1 counter on Makeshift Battalion.

Boros Guildgate

Boros Guildgate enters the battlefield tapped.
{T}: Add {R} or {W}.

Swathcutter Giant

Vigilance
Whenever Swathcutter Giant attacks, it deals 1 damage to each creature defending player controls.

Legion Loyalist

Haste
Battalion — Whenever Legion Loyalist and at least two other creatures attack, creatures you control gain first strike and trample until end of turn and can't be blocked by creature tokens this turn.