Cavalry Drillmaster

When Cavalry Drillmaster enters, target creature gets +2/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Lightning Helix

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

Martial Glory

Target creature gets +3/+0 until end of turn.
Target creature gets +0/+3 until end of turn.

Boros Signet

Joust

Choose target creature you control and target creature you don't control. The creature you control gets +2/+1 until end of turn if it's a Knight. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Brimstone Trebuchet

Defender, reach
{T}: Brimstone Trebuchet deals 1 damage to each opponent.
Whenever a Knight you control enters, untap Brimstone Trebuchet.

Mountain

Gird for Battle

Put a +1/+1 counter on each of up to two target creatures.

Acclaimed Contender

When Acclaimed Contender enters, if you control another Knight, look at the top five cards of your library. You may reveal a Knight, Aura, Equipment, or legendary artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Inspiring Veteran

Plains

Venerable Knight

When Venerable Knight dies, put a +1/+1 counter on target Knight you control.

Skyknight Legionnaire

Temple of Triumph

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {R} or {W}.

Dizzying Swoop

Tap up to two target creatures. (Then exile this card. You may cast the creature later from exile.)

Ardenvale Tactician

Ardenvale Tactician // Dizzying Swoop

Weaselback Redcap

{1}{R}: Weaselback Redcap gets +2/+0 until end of turn.

Boros Garrison

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

Shock

Wind-Scarred Crag

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

Boulder Rush

Target creature gets +2/+0 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Rimrock Knight

Rimrock Knight // Boulder Rush

Truefire Captain

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Truefire Captain is dealt damage, it deals that much damage to target player.