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.

Furnace of Rath

If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Mountain

Goblin Warchief

Goblin spells you cast cost {1} less to cast.
Goblins you control have haste.

Volley Veteran

When this creature enters, it deals damage to target creature an opponent controls equal to the number of Goblins you control.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Goblin Trashmaster

Other Goblins you control get +1/+1.
Sacrifice a Goblin: Destroy target artifact.

Outnumber

Outnumber deals damage to target creature equal to the number of creatures you control.

Goblin War Strike

Goblin War Strike deals damage to target player or planeswalker equal to the number of Goblins you control.

Shock

Goblin Arsonist

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

Brightstone Ritual

Add {R} for each Goblin on the battlefield.

Sparksmith

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

Violent Impact

Destroy target artifact or land.
Cycling {2} ({2}, Discard this card: Draw a card.)

Impact Tremors

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

Goblin Motivator

{T}: Target creature gains haste until end of turn. (It can attack and {T} this turn.)

Goblin Sharpshooter

Goblin Sharpshooter doesn't untap during your untap step.
Whenever a creature dies, untap Goblin Sharpshooter.
{T}: Goblin Sharpshooter deals 1 damage to any target.

Smelt

Relentless Assault

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Krenko, Tin Street Kingpin

Whenever Krenko, Tin Street Kingpin attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Goblin Caves

Enchant land
As long as enchanted land is a basic Mountain, Goblin creatures get +0/+2.

Expedite

Target creature gains haste until end of turn.
Draw a card.

Skirk Prospector

Boggart Brute

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

Krenko's Command

Create two 1/1 red Goblin creature tokens.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Legion Warboss

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
At the beginning of combat on your turn, create a 1/1 red Goblin creature token. That token gains haste until end of turn and attacks this combat if able.

Rummaging Goblin

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Goblin Chirurgeon

Sacrifice a Goblin: Regenerate target creature.

Squee, Goblin Nabob

At the beginning of your upkeep, you may return Squee, Goblin Nabob from your graveyard to your hand.

Goblin King

Other Goblins get +1/+1 and have mountainwalk.

Squee, the Immortal

You may cast Squee, the Immortal from your graveyard or from exile.

Crash Through

Creatures you control gain trample until end of turn. (Each of those creature can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

Goblin Diplomats

{T}: Each creature attacks this turn if able.

Dragon Fodder

Preyseizer Dragon

Flying
Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
Whenever Preyseizer Dragon attacks, it deals damage to any target equal to the number of +1/+1 counters on Preyseizer Dragon.

Goblin Grenade

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

Krenko, Mob Boss

{T}: Create X 1/1 red Goblin creature tokens, where X is the number of Goblins you control.

Goblin Javelineer

Haste
Whenever Goblin Javelineer becomes blocked, it deals 1 damage to target creature blocking it.

Frenzied Goblin

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

Massive Raid

Massive Raid deals damage to any target equal to the number of creatures you control.