Have

Gempalm Incinerator

Cycling {1}{R} ({1}{R}, Discard this card: Draw a card.)
When you cycle Gempalm Incinerator, you may have it deal X damage to target creature, where X is the number of Goblins on the battlefield.

Brightstone Ritual

Add {R} for each Goblin on the battlefield.

Goblin Spy

Play with the top card of your library revealed.

Goblin Wardriver

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

Goblin Arsonist

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

Goblin Spelunkers

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)

Goblin Warchief

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

Bloodmark Mentor

Red creatures you control have first strike.

Skirk Prospector

Goblin Burrows

{T}: Add {C}.
{1}{R}, {T}: Target Goblin creature gets +2/+0 until end of turn.

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.

Goblin Grenade

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

Mountain

Goblin Psychopath

Whenever Goblin Psychopath attacks or blocks, flip a coin. If you lose the flip, the next time it would deal combat damage this turn, it deals that damage to you instead.

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.

Goblin War Strike

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

Quest for Pure Flame

Whenever a source you control deals damage to an opponent, you may put a quest counter on Quest for Pure Flame.
Remove four quest counters from Quest for Pure Flame and sacrifice it: If any source you control would deal damage to a permanent or player this turn, it deals double that damage to that permanent or player instead.

Squee, Goblin Nabob

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

Ib Halfheart, Goblin Tactician

Whenever another Goblin you control becomes blocked, sacrifice it. If you do, it deals 4 damage to each creature blocking it.
Sacrifice two Mountains: Create two 1/1 red Goblin creature tokens.

Goblin Balloon Brigade

{R}: Goblin Balloon Brigade gains flying until end of turn.

Tuktuk the Explorer

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

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.

Voracious Dragon

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