Mountain

Flame Slash

Flame Slash deals 4 damage to target creature.

Mudbrawler Cohort

Haste
This creature gets +1/+1 as long as you control another red creature.

Fireblast

You may sacrifice two Mountains rather than pay this spell's mana cost.
Fireblast deals 4 damage to any target.

Gorilla Shaman

{X}{X}{1}: Destroy target noncreature artifact with mana value X.

Goblin Heelcutter

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

Mogg Conscripts

This creature can't attack unless you've cast a creature spell this turn.

Foundry Street Denizen

Whenever another red creature you control enters, this creature gets +1/+0 until end of turn.

Chain Lightning

Chain Lightning deals 3 damage to any target. Then that player or that permanent's controller may pay {R}{R}. If the player does, they may copy this spell and may choose a new target for that copy.

Jackal Familiar

This creature can't attack or block alone.

Burning-Tree Emissary

Goblin Grenade

As an additional cost to cast this spell, sacrifice a Goblin.
Goblin Grenade deals 5 damage to any target.

Valley Dasher

Haste
This creature attacks each combat if able.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Electrickery

Electrickery deals 1 damage to target creature you don't control.
Overload {1}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Goblin Cohort

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Sparksmith

{T}: This creature deals X damage to target creature and X damage to you, where X is the number of Goblins on the battlefield.

Goblin Bushwhacker

Kicker {R} (You may pay an additional {R} as you cast this spell.)
When this creature enters, if it was kicked, creatures you control get +1/+0 and gain haste until end of turn.

Boulder Rush

Target creature gets +2/+0 until end of turn. (Then exile this card. You may cast the creature later from exile.)