Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Foundry Street Denizen

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

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Goblin Lackey

Whenever Goblin Lackey deals damage to a player, you may put a Goblin permanent card from your hand onto the battlefield.

Feldon's Cane

{T}, Exile this artifact: Shuffle your graveyard into your library.

Goblin Warchief

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

Ashnod's Altar

Goblin Ringleader

Haste (This creature can attack and {T} as soon as it comes under your control.)
When Goblin Ringleader enters, reveal the top four cards of your library. Put all Goblin cards revealed this way into your hand and the rest on the bottom of your library in any order.

Blood Aspirant

Whenever you sacrifice a permanent, put a +1/+1 counter on Blood Aspirant.
{1}{R}, {T}, Sacrifice a creature or enchantment: Blood Aspirant deals 1 damage to target creature. That creature can't block this turn.

Sorcerer's Broom

Whenever you sacrifice another permanent, you may pay {3}. If you do, create a token that's a copy of Sorcerer's Broom.

Bubbling Cauldron

{1}, {T}, Sacrifice a creature: You gain 4 life.
{1}, {T}, Sacrifice a creature named Festering Newt: Each opponent loses 4 life. You gain life equal to the life lost this way.

Jinxed Idol

At the beginning of your upkeep, Jinxed Idol deals 2 damage to you.
Sacrifice a creature: Target opponent gains control of Jinxed Idol.

Mogg Infestation

Destroy all creatures target player controls. For each creature that died this way, that player creates two 1/1 red Goblin creature tokens.

Helm of Possession

You may choose not to untap Helm of Possession during your untap step.
{2}, {T}, Sacrifice a creature: Gain control of target creature for as long as you control Helm of Possession and Helm of Possession remains tapped.

Cheering Fanatic

Whenever Cheering Fanatic attacks, choose a card name. Spells with the chosen name cost {1} less to cast this turn.

Goblin Assassin

Whenever Goblin Assassin or another Goblin enters, each player flips a coin. Each player whose coin comes up tails sacrifices a creature of their choice.

Aetherworks Marvel

Whenever a permanent you control is put into a graveyard, you get {E} (an energy counter).
{T}, Pay six {E}: Look at the top six cards of your library. You may cast a spell from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

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 Chirurgeon

Sacrifice a Goblin: Regenerate target creature.

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.

Cranial Archive

{2}, Exile Cranial Archive: Target player shuffles their graveyard into their library. Draw a card.

Squee, the Immortal

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

The Immortal Sun

Players can't activate planeswalkers' loyalty abilities.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.
Creatures you control get +1/+1.

Gremlin Infestation

Enchant artifact
At the beginning of your end step, Gremlin Infestation deals 2 damage to enchanted artifact's controller.
When enchanted artifact is put into a graveyard, create a 2/2 red Gremlin creature token.

Dark-Dweller Oracle

{1}, Sacrifice a creature: Exile the top card of your library. You may play that card this turn. (You still pay its costs. You can play a land this way only if you have an available land play remaining.)

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Havoc Jester

Whenever you sacrifice a permanent, Havoc Jester deals 1 damage to any target.

Spawning Pit

Sacrifice a creature: Put a charge counter on Spawning Pit.
{1}, Remove two charge counters from Spawning Pit: Create a 2/2 colorless Spawn artifact creature token.

Shivan Harvest

{1}{R}, Sacrifice a creature: Destroy target nonbasic land.

Goblin Smuggler

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}: Another target creature with power 2 or less can't be blocked this turn.

Mountain

Goblin Traprunner

Whenever Goblin Traprunner attacks, flip three coins. For each flip you win, create a 1/1 red Goblin creature token that's tapped and attacking.

Arms Dealer

{1}{R}, Sacrifice a Goblin: Arms Dealer deals 4 damage to target creature.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Goblin Sappers

{R}{R}, {T}: Target creature you control can't be blocked this turn. Destroy it and Goblin Sappers at end of combat.
{R}{R}{R}{R}, {T}: Target creature you control can't be blocked this turn. Destroy it at end of combat.

Goblin Soothsayer

{R}, {T}, Sacrifice a Goblin: Red creatures get +1/+1 until end of turn.

Battle Cry Goblin

{1}{R}: Goblins you control get +1/+0 and gain haste until end of turn.
Whenever Battle Cry Goblin attacks, if you attacked with creatures with total power 6 or greater this combat, create a 1/1 red Goblin creature token that's tapped and attacking.

Krenko, Mob Boss

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

Goblin Battle Jester

Whenever you cast a red spell, target creature can't block this turn.

Madblind Mountain

({T}: Add {R}.)
Madblind Mountain enters tapped.
{R}, {T}: Shuffle your library. Activate only if you control two or more red permanents.

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.

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.

Tuktuk the Explorer

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

Skirk Prospector

Runaway Steam-Kin

Whenever you cast a red spell, if Runaway Steam-Kin has fewer than three +1/+1 counters on it, put a +1/+1 counter on Runaway Steam-Kin.
Remove three +1/+1 counters from Runaway Steam-Kin: Add {R}{R}{R}.

Kiki-Jiki, Mirror Breaker

Haste
{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Goblin Spy

Play with the top card of your library revealed.

Goblin Sledder

Sacrifice a Goblin: Target creature gets +1/+1 until end of turn.

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.

Goblin Lookout

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

Diamond Valley

{T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Conspicuous Snoop

Play with the top card of your library revealed.
You may cast Goblin spells from the top of your library.
As long as the top card of your library is a Goblin card, Conspicuous Snoop has all activated abilities of that card.

Elixir of Immortality

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

Jinxed Ring

Whenever a nontoken permanent is put into your graveyard from the battlefield, Jinxed Ring deals 1 damage to you.
Sacrifice a creature: Target opponent gains control of Jinxed Ring. (This effect lasts indefinitely.)

Den of the Bugbear

If you control two or more other lands, Den of the Bugbear enters tapped.
{T}: Add {R}.
{3}{R}: Until end of turn, Den of the Bugbear becomes a 3/2 red Goblin creature with "Whenever this creature attacks, create a 1/1 red Goblin creature token that's tapped and attacking." It's still a land.