Anger

Haste
As long as this card is in your graveyard and you control a Mountain, creatures you control have haste.

Seething Song

Krenko, Mob Boss

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

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Goblin Matron

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

Ruby Medallion

Red spells you cast cost {1} less to cast.

Mountain

Seize the Spoils

As an additional cost to cast this spell, discard a card.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Slate of Ancestry

{4}, {T}, Discard your hand: Draw a card for each creature you control.

Muxus, Goblin Grandee

When Muxus enters, reveal the top six cards of your library. Put all Goblin creature cards with mana value 5 or less from among them onto the battlefield and the rest on the bottom of your library in a random order.
Whenever Muxus attacks, it gets +1/+1 until end of turn for each other Goblin you control.

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Moria Marauder

Double strike
Whenever a Goblin or Orc you control deals combat damage to a player, exile the top card of your library. You may play that card this turn.

Skirk Prospector

Witchstalker Frenzy

This spell costs {1} less to cast for each creature that attacked this turn.
Witchstalker Frenzy deals 5 damage to target creature.

Mark of Mutiny

Gain control of target creature until end of turn. Put a +1/+1 counter on it and untap it. That creature gains haste until end of turn. (It can attack and {T} this turn.)

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.