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.

Goblin Goliath

When Goblin Goliath enters, create a number of 1/1 red Goblin creature tokens equal to the number of opponents you have.
{3}{R}, {T}: If a source you control would deal damage to an opponent this turn, it deals double that damage to that player instead.

Caterwauling Boggart

Goblins you control and Elementals you control have menace. (They can't be blocked except by two or more creatures.)

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.

Frogtosser Banneret

Haste
Goblin spells and Rogue spells you cast cost {1} less to cast.

Goblin Warrens

{2}{R}, Sacrifice two Goblins: Create three 1/1 red Goblin creature tokens.

Goblin Lookout

{T}, Sacrifice a Goblin: Goblin creatures get +2/+0 until end of turn.

Goblin Caves

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

Mad Auntie

Other Goblin creatures you control get +1/+1.
{T}: Regenerate another target Goblin.

Goblin Matron

When Goblin Matron enters, you may search your library for a Goblin card, reveal that card, put it into your hand, then shuffle.

Munitions Expert

Flash
When Munitions Expert enters, you may have it deal damage to target creature or planeswalker equal to the number of Goblins you control.

Weirding Shaman

{3}{B}, Sacrifice a Goblin: Create two 1/1 black Goblin Rogue creature tokens.

Goblin Warchief

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

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.

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 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 Goblin Rabblemaster attacks, it gets +1/+0 until end of turn for each other attacking Goblin.

Bloodmark Mentor

Red creatures you control have first strike.

Reckless Bushwhacker

Surge {1}{R} (You may cast this spell for its surge cost if you or a teammate has cast another spell this turn.)
Haste
When Reckless Bushwhacker enters, if its surge cost was paid, other creatures you control get +1/+0 and gain haste until end of turn.

Legion Loyalist

Haste
Battalion — Whenever Legion Loyalist and at least two other creatures attack, creatures you control gain first strike and trample until end of turn and can't be blocked by creature tokens this turn.

Volley Veteran

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

Pashalik Mons

Whenever Pashalik Mons or another Goblin you control dies, Pashalik Mons deals 1 damage to any target.
{3}{R}, Sacrifice a Goblin: Create two 1/1 red Goblin creature tokens.

Goblin Trashmaster

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

Shared Animosity

Whenever a creature you control attacks, it gets +1/+0 until end of turn for each other attacking creature that shares a creature type with it.

Reckless One

Haste
Reckless One's power and toughness are each equal to the number of Goblins on the battlefield.

Goblin Wardriver

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)

Goblin Chainwhirler

First strike
When Goblin Chainwhirler enters, it deals 1 damage to each opponent and each creature and planeswalker they control.

Boggart Harbinger

When Boggart Harbinger enters, you may search your library for a Goblin card, reveal it, then shuffle and put that card on top.

Goblin Instigator

When Goblin Instigator enters, create a 1/1 red Goblin creature token.

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.

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.

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.

Wort, Boggart Auntie

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
At the beginning of your upkeep, you may return target Goblin card from your graveyard to your hand.

Goblin King

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

Goblin Piledriver

Protection from blue (This creature can't be blocked, targeted, dealt damage, or enchanted by anything blue.)
Whenever Goblin Piledriver attacks, it gets +2/+0 until end of turn for each other attacking Goblin.

Sensation Gorger

Kinship — At the beginning of your upkeep, you may look at the top card of your library. If it shares a creature type with Sensation Gorger, you may reveal it. If you do, each player discards their hand, then draws four cards.

Boggart Mob

Champion a Goblin (When this enters, sacrifice it unless you exile another Goblin you control. When this leaves the battlefield, that card returns to the battlefield.)
Whenever a Goblin you control deals combat damage to a player, you may create a 1/1 black Goblin Rogue creature token.

Warren Instigator

Double strike
Whenever Warren Instigator deals damage to an opponent, you may put a Goblin creature card from your hand onto the battlefield.

Beetleback Chief

When Beetleback Chief enters, create two 1/1 red Goblin creature tokens.

Warren Pilferers

When Warren Pilferers enters, return target creature card from your graveyard to your hand. If that card is a Goblin card, Warren Pilferers gains haste until end of turn.

Cabal Slaver

Whenever a Goblin deals combat damage to a player, that player discards a card.

Skirk Drill Sergeant

Whenever Skirk Drill Sergeant or another Goblin dies, you may pay {2}{R}. If you do, reveal the top card of your library. If it's a Goblin permanent card, put it onto the battlefield. Otherwise, put it into your graveyard.

Dralnu's Crusade

All Goblins get +1/+1.
All Goblins are black and are Zombies in addition to their other creature types.

Fervor

Creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

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.

Goblin War Drums

Creatures you control have menace. (They can't be blocked except by two or more creatures.)

Battle Squadron

Flying
Battle Squadron's power and toughness are each equal to the number of creatures you control.

Metallic Mimic

As Metallic Mimic enters, choose a creature type.
Metallic Mimic is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

Grenzo, Dungeon Warden

Grenzo, Dungeon Warden enters with X +1/+1 counters on it.
{2}: Put the bottom card of your library into your graveyard. If it's a creature card with power less than or equal to Grenzo's power, put it onto the battlefield.

Krenko, Mob Boss

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

Knucklebone Witch

Whenever a Goblin you control is put into a graveyard from the battlefield, you may put a +1/+1 counter on Knucklebone Witch.

Chancellor of the Forge

You may reveal this card from your opening hand. If you do, at the beginning of the first upkeep, create a 1/1 red Phyrexian Goblin creature token with haste.
When Chancellor of the Forge enters, create X 1/1 red Phyrexian Goblin creature tokens with haste, where X is the number of creatures you control.

Mana Echoes

Whenever a creature enters, you may add an amount of {C} equal to the number of creatures you control that share a creature type with it.