Borrowed Hostility

Escalate {3} (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Target creature gets +3/+0 until end of turn.
• Target creature gains first strike until end of turn.

Krenko's Command

Create two 1/1 red Goblin creature tokens.

Chandra, Roaring Flame

+1: Chandra deals 2 damage to target player or planeswalker.
−2: Chandra deals 2 damage to target creature.
−7: Chandra deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

Chandra, Fire of Kaladesh

Whenever you cast a red spell, untap Chandra.
{T}: Chandra deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Chandra, Fire of Kaladesh // Chandra, Roaring Flame

Thundering Rebuke

Thundering Rebuke deals 4 damage to target creature or planeswalker.

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.

Relic Robber

Haste
Whenever this creature deals combat damage to a player, that player creates a 0/1 colorless Goblin Construct artifact creature token with "This token can't block" and "At the beginning of your upkeep, this token deals 1 damage to you."

Outnumber

Outnumber deals damage to target creature equal to the number of creatures you control.

Vessel of Volatility

{1}{R}, Sacrifice this enchantment: Add {R}{R}{R}{R}.

Beetleback Chief

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

Battle Cry Goblin

{1}{R}: Goblins you control get +1/+0 and gain haste until end of turn.
Pack tactics — Whenever this creature 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.

Goblin Piledriver

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

Fiery Conclusion

As an additional cost to cast this spell, sacrifice a creature.
Fiery Conclusion deals 5 damage to target creature.

Valakut Exploration

Landfall — Whenever a land you control enters, exile the top card of your library. You may play that card for as long as it remains exiled.
At the beginning of your end step, if there are cards exiled with this enchantment, put them into their owner's graveyard, then this enchantment deals that much damage to each opponent.

Sure Strike

Target creature gets +3/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Goblin Bombardment

Sacrifice a creature: This enchantment deals 1 damage to any target.

Hammer of Purphoros

Creatures you control have haste.
{2}{R}, {T}, Sacrifice a land: Create a 3/3 colorless Golem enchantment artifact creature token.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Ogre Battledriver

Whenever another creature you control enters, that creature gets +2/+0 and gains haste until end of turn. (It can attack and {T} this turn.)

Valakut, the Molten Pinnacle

This land enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target.
{T}: Add {R}.

Hobgoblin Bandit Lord

Other Goblins you control get +1/+1.
{R}, {T}: This creature deals damage equal to the number of Goblins that entered the battlefield under your control this turn to any target.

Den of the Bugbear

If you control two or more other lands, this land enters tapped.
{T}: Add {R}.
{3}{R}: Until end of turn, this land 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.

Krenko, Mob Boss

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

Goblin Morningstar

Equipped creature gets +1/+0 and has trample.
Equip {1}{R}
When this Equipment enters, roll a d20.
1—9 | Create a 1/1 red Goblin creature token.
10—20 | Create a 1/1 red Goblin creature token, then attach this Equipment to it.

Mountain

Exquisite Firecraft

Exquisite Firecraft deals 4 damage to any target.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, this spell can't be countered.

Zariel, Archduke of Avernus

+1: Creatures you control get +1/+0 and gain haste until end of turn.
0: Create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."
−6: You get an emblem with "At the end of the first combat phase on your turn, untap target creature you control. After this phase, there is an additional combat phase."

Ordeal of Purphoros

Enchant creature
Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice this Aura.
When you sacrifice this Aura, it deals 3 damage to any target.

Dragon Fodder

Rigging Runner

First strike
Raid — This creature enters with a +1/+1 counter on it if you attacked this turn.

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