Bloodmark Mentor

Red creatures you control have first strike.

Dragon Fodder

Create two 1/1 red Goblin creature tokens.

Shock

Horde of Boggarts

Menace (This creature can't be blocked except by two or more creatures.)
Horde of Boggarts's power and toughness are each equal to the number of red permanents you control.

War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.

Mountain

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Flashfires

Goblin Assault

At the beginning of your upkeep, create a 1/1 red Goblin creature token with haste.
Goblin creatures attack each combat if able.

Empty the Warrens

Create two 1/1 red Goblin creature tokens.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Goblin Chieftain

Haste (This creature can attack and {T} as soon as it comes under your control.)
Other Goblin creatures you control get +1/+1 and have haste.

Goblin Guide

Haste
Whenever Goblin Guide attacks, defending player reveals the top card of their library. If it's a land card, that player puts it into their hand.

Siege-Gang Commander

When Siege-Gang Commander enters, create three 1/1 red Goblin creature tokens.
{1}{R}, Sacrifice a Goblin: Siege-Gang Commander deals 2 damage to any target.

Bazaar Trader

{T}: Target player gains control of target artifact, creature, or land you control.

Aether Membrane

Defender; reach (This creature can block creatures with flying.)
Whenever Aether Membrane blocks a creature, return that creature to its owner's hand at end of combat.

Goblin Arsonist

When Goblin Arsonist dies, you may have it deal 1 damage to any target.

Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Goblin Mountaineer

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)

Tuktuk the Explorer

Haste
When Tuktuk the Explorer dies, create Tuktuk the Returned, a legendary 5/5 colorless Goblin Golem artifact creature token.

Demonfire

Demonfire deals X damage to any target. If a creature dealt damage this way would die this turn, exile it instead.
Hellbent — If you have no cards in hand, this spell can't be countered and the damage can't be prevented.

Smoldering Spires

Smoldering Spires enters tapped.
When Smoldering Spires enters, target creature can't block this turn.
{T}: Add {R}.

Frenzied Goblin

Whenever this creature attacks, you may pay {R}. If you do, target creature can't block this turn.

Searing Blaze

Searing Blaze deals 1 damage to target player or planeswalker and 1 damage to target creature that player or that planeswalker's controller controls.
Landfall — If you had a land enter the battlefield under your control this turn, Searing Blaze deals 3 damage to that player or planeswalker and 3 damage to that creature instead.

Red Sun's Zenith

Red Sun's Zenith deals X damage to any target. If a creature dealt damage this way would die this turn, exile it instead. Shuffle Red Sun's Zenith into its owner's library.

Raging Goblin

Haste (This creature can attack and {T} as soon as it comes under your control.)

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on this creature.

Boggart Shenanigans

Whenever another Goblin you control is put into a graveyard from the battlefield, you may have Boggart Shenanigans deal 1 damage to target player or planeswalker.

Boiling Seas

Tattermunge Maniac

Tattermunge Maniac attacks each combat if able.

Quest for the Goblin Lord

Whenever a Goblin you control enters, you may put a quest counter on Quest for the Goblin Lord.
As long as Quest for the Goblin Lord has five or more quest counters on it, creatures you control get +2/+0.