Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."

Goblin Banneret

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
{1}{R}: This creature gets +2/+0 until end of turn.

Skirk Prospector

Krenko, Tin Street Kingpin

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

Siege-Gang Commander

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

Wily Goblin

When this creature enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Lava Coil

Lava Coil deals 4 damage to target creature. If that creature would die this turn, exile it instead.

Chandra, Fire Artisan

Whenever one or more loyalty counters are removed from Chandra, she deals that much damage to target opponent or planeswalker.
+1: Exile the top card of your library. You may play it this turn.
−7: Exile the top seven cards of your library. You may play them this turn.

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.)

Jaya, Venerated Firemage

If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
−2: Jaya deals 2 damage to any target.

Goblin Trashmaster

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

Goblin Warchief

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

Fanatical Firebrand

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}, Sacrifice this creature: It deals 1 damage to any target.

Mountain

Goblin Chainwhirler

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

Goblin Instigator

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

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.