Plains

Azorius Arrester

When Azorius Arrester enters, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Orzhov Guildgate

Orzhov Guildgate enters tapped.
{T}: Add {W} or {B}.

Vulturous Aven

Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Vulturous Aven exploits a creature, you draw two cards and you lose 2 life.

Akoum Refuge

Akoum Refuge enters tapped.
When Akoum Refuge enters, you gain 1 life.
{T}: Add {B} or {R}.

Scoured Barrens

Scoured Barrens enters tapped.
When Scoured Barrens enters, you gain 1 life.
{T}: Add {W} or {B}.

Searing Spear

Searing Spear deals 3 damage to any target.

Bone Splinters

As an additional cost to cast this spell, sacrifice a creature.
Destroy target creature.

Sin Collector

When Sin Collector enters, target opponent reveals their hand. You choose an instant or sorcery card from it and exile that card.

Boros Guildgate

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

Sibsig Icebreakers

When Sibsig Icebreakers enters, each player discards a card.

Mountain

Minister of Pain

Exploit (When this creature enters, you may sacrifice a creature.)
When Minister of Pain exploits a creature, creatures your opponents control get -1/-1 until end of turn.

Swamp

Alesha, Who Smiles at Death

First strike
Whenever Alesha, Who Smiles at Death 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.

Sandsteppe Outcast

When Sandsteppe Outcast enters, choose one —
• Put a +1/+1 counter on Sandsteppe Outcast.
• Create a 1/1 white Spirit creature token with flying.

Mardu Heart-Piercer

Raid — When Mardu Heart-Piercer enters, if you attacked this turn, Mardu Heart-Piercer deals 2 damage to any target.