Aven Skirmisher

Chief of the Edge

Other Warrior creatures you control get +1/+0.

Chief of the Scale

Other Warrior creatures you control get +0/+1.

Mardu Ascendancy

Whenever a nontoken creature you control attacks, create a 1/1 red Goblin creature token that's tapped and attacking.
Sacrifice Mardu Ascendancy: Creatures you control get +0/+3 until end of turn.

Plains

Mardu Warshrieker

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

Flatten

Target creature gets -4/-4 until end of turn.

Herald of Dromoka

Vigilance
Other Warrior creatures you control have vigilance.

Lightning Shrieker

Flying, trample, haste
At the beginning of the end step, Lightning Shrieker's owner shuffles it into their library.

Sorin, Solemn Visitor

+1: Until your next turn, creatures you control get +1/+0 and gain lifelink.
−2: Create a 2/2 black Vampire creature token with flying.
−6: You get an emblem with "At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice."

Suspension Field

When Suspension Field enters, you may exile target creature with toughness 3 or greater until Suspension Field leaves the battlefield. (That creature returns under its owner's control.)

Roast

Roast deals 5 damage to target creature without flying.

Wind-Scarred Crag

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

Sage-Eye Harrier

Flying
Morph {3}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Salt Road Patrol

Outlast {1}{W} ({1}{W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)

Swamp

Mountain

Bloodfell Caves

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

Murderous Cut

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Destroy target creature.

Molting Snakeskin

Enchant creature
Enchanted creature gets +2/+0 and has "{2}{B}: Regenerate this creature."

Kolaghan, the Storm's Fury

Flying
Whenever a Dragon you control attacks, creatures you control get +1/+0 until end of turn.
Dash {3}{B}{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.)

Disowned Ancestor

Outlast {1}{B} ({1}{B}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)