Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Plains

Mardu Warshrieker

Raid — When Mardu Warshrieker enters, if you attacked this turn, add {R}{W}{B}.

Ambuscade Shaman

Whenever Ambuscade Shaman or another creature you control enters, that creature gets +2/+2 until end of turn.
Dash {3}{B} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Screamreach Brawler

Dash {1}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Cinder Barrens

Cinder Barrens enters tapped.
{T}: Add {B} or {R}.

Pitiless Horde

At the beginning of your upkeep, you lose 2 life.
Dash {2}{B}{B} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Dire Fleet Ravager

Menace, deathtouch
When Dire Fleet Ravager enters, each player loses a third of their life, rounded up.

Mardu Roughrider

Whenever Mardu Roughrider attacks, target creature can't block this turn.

Alesha's Vanguard

Dash {2}{B} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Sprinting Warbrute

Sprinting Warbrute attacks each combat if able.
Dash {3}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Foul-Tongue Shriek

Target opponent loses 1 life for each attacking creature you control. You gain that much life.

Warbringer

Dash costs you pay cost {2} less (as long as this creature is on the battlefield).
Dash {2}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Mountain

Zurgo Bellstriker

Zurgo Bellstriker can't block creatures with power 2 or greater.
Dash {1}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

Brutal Hordechief

Whenever a creature you control attacks, defending player loses 1 life and you gain 1 life.
{3}{R/W}{R/W}: Creatures your opponents control block this turn if able, and you choose how those creatures block.

Mardu Banner

{T}: Add {R}, {W}, or {B}.
{R}{W}{B}, {T}, Sacrifice Mardu Banner: Draw a card.

Swamp

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Zurgo Helmsmasher

Haste
Zurgo Helmsmasher attacks each combat if able.
During your turn, Zurgo Helmsmasher has indestructible.
Whenever a creature dealt damage by Zurgo Helmsmasher this turn dies, put a +1/+1 counter on Zurgo Helmsmasher.