Boros Reckoner

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.

Gideon's Sacrifice

Choose a creature or planeswalker you control. All damage that would be dealt this turn to you and permanents you control is dealt to the chosen permanent instead (if it's still on the battlefield).

Reckless Rage

Reckless Rage deals 4 damage to target creature you don't control and 2 damage to target creature you control.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Clifftop Retreat

Clifftop Retreat enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

Mountain

Tilonalli's Crown

Enchant creature
When Tilonalli's Crown enters, it deals 1 damage to enchanted creature.
Enchanted creature gets +3/+0 and has trample.

Plains

Sundown Pass

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Stormwild Capridor

Flying
If noncombat damage would be dealt to Stormwild Capridor, prevent that damage. Put a +1/+1 counter on Stormwild Capridor for each 1 damage prevented this way.

Rugged Prairie

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

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Marauding Raptor

Creature spells you cast cost {1} less to cast.
Whenever another creature you control enters, Marauding Raptor deals 2 damage to it. If a Dinosaur is dealt damage this way, Marauding Raptor gets +2/+0 until end of turn.

Rile

Rile deals 1 damage to target creature you control. That creature gains trample until end of turn.
Draw a card.

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.

Phyrexian Vindicator

Flying
If damage would be dealt to Phyrexian Vindicator, prevent that damage. When damage is prevented this way, Phyrexian Vindicator deals that much damage to any other target.