Howl of the Horde

When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.
Raid — If you attacked this turn, when you next cast an instant or sorcery spell this turn, copy that spell an additional time. You may choose new targets for the copy.

Mountain

Alesha, Who Smiles at Death

First strike
Whenever Alesha attacks, you may pay {W/B}{W/B}. If you do, return target creature card with power 2 or less from your graveyard to the battlefield tapped and attacking.

Nomad Outpost

This land enters tapped.
{T}: Add {R}, {W}, or {B}.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. This land deals 1 damage to you.

Unforgiving One

Menace (This creature can't be blocked except by two or more creatures.)
Whenever this creature attacks, return target creature card with mana value X or less from your graveyard to the battlefield, where X is the number of modified creatures you control. (Equipment, Auras you control, and counters are modifications.)

Bloodsoaked Champion

This creature can't block.
Raid — {1}{B}: Return this card from your graveyard to the battlefield. Activate only if you attacked this turn.

Crumbling Necropolis

This land enters tapped.
{T}: Add {U}, {B}, or {R}.

Island

Timely Hordemate

Raid — When this creature enters, if you attacked this turn, return target creature card with mana value 2 or less from your graveyard to the battlefield.

Firecannon Blast

Firecannon Blast deals 3 damage to target creature.
Raid — Firecannon Blast deals 6 damage instead if you attacked this turn.

Plains

Raiders' Wake

Whenever an opponent discards a card, that player loses 2 life.
Raid — At the beginning of your end step, if you attacked this turn, target opponent discards a card.

Repeating Barrage

Repeating Barrage deals 3 damage to any target.
Raid — {3}{R}{R}: Return this card from your graveyard to your hand. Activate only if you attacked this turn.

Storm Fleet Aerialist

Flying
Raid — This creature enters with a +1/+1 counter on it if you attacked this turn.

Brazen Cannonade

Whenever an attacking creature you control dies, this enchantment deals 2 damage to each opponent.
Raid — At the beginning of each of your postcombat main phases, if you attacked this turn, exile the top card of your library. Until end of combat on your next turn, you may play that card.

Cult Conscript

This creature enters tapped.
{1}{B}: Return this card from your graveyard to the battlefield. Activate only if a non-Skeleton creature died under your control this turn.

Rigging Runner

First strike
Raid — This creature enters with a +1/+1 counter on it if you attacked this turn.

Heartless Pillage

Target opponent discards two cards.
Raid — If you attacked this turn, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Protean Raider

Raid — If you attacked this turn, you may have this creature enter as a copy of any creature on the battlefield.