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Boldwyr Intimidator

Cowards can't block Warriors.
{R}: Target creature becomes a Coward until end of turn.
{2}{R}: Target creature becomes a Warrior until end of turn.

Kargan Intimidator

Cowards can't block Warriors.
{1}: Choose one that hasn't been chosen this turn —
• This creature gets +1/+1 until end of turn.
• Target creature becomes a Coward until end of turn.
• Target Warrior gains trample until end of turn.

Soul Sear

Soul Sear deals 5 damage to target creature or planeswalker. That permanent loses indestructible until end of turn.

Gornog, the Red Reaper

Haste
Cowards can't block Warriors.
Whenever one or more Warriors you control attack a player, target creature that player controls becomes a Coward.
Attacking Warriors you control get +X/+0, where X is the number of Cowards your opponents control.

Mountain

Daybreak Combatants

Haste (This creature can attack and {T} as soon as it comes under your control.)
When this creature enters, target creature gets +2/+0 until end of turn.

Goma Fada Vanguard

Whenever this creature attacks, target creature an opponent controls with power less than or equal to the number of Warriors you control can't block this turn.

Pyrophobia

Pyrophobia deals 3 damage to target creature. Cowards can't block this turn.

Thriving Bluff

This land enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Boggart Brute

Menace (This creature can't be blocked except by two or more creatures.)

Goblin Rabblemaster

Other Goblin creatures you control attack each combat if able.
At the beginning of combat on your turn, create a 1/1 red Goblin creature token with haste.
Whenever this creature attacks, it gets +1/+0 until end of turn for each other attacking Goblin.

Infuriate

Target creature gets +3/+2 until end of turn.

Kindled Fury

Target creature gets +1/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Ghitu Encampment

This land enters tapped.
{T}: Add {R}.
{1}{R}: This land becomes a 2/1 red Warrior creature with first strike until end of turn. It's still a land. (It deals combat damage before creatures without first strike.)

Warriors

Wrecking Crew

Reach (This creature can block creatures with flying.)
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)