Loyal Sentry

When Loyal Sentry blocks a creature, destroy that creature and Loyal Sentry.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Vigilance
Trusty Companion can't attack alone.

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Create three 1/1 white Soldier creature tokens.

Flying
War Falcon can't attack unless you control a Knight or a Soldier.

Create two 1/1 colorless Myr artifact creature tokens.

Enchant creature
Enchanted creature can't attack or block.

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

Whenever Boros Reckoner is dealt damage, it deals that much damage to any target.
{R/W}: Boros Reckoner gains first strike until end of turn.

First strike
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)

When Hunted Witness dies, create a 1/1 white Soldier creature token with lifelink.

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

Target creature gets +2/+2 and gains flying until end of turn. You gain 2 life.