Mountain

Dragon Fodder

Create two 1/1 red Goblin creature tokens.

Goblin Assault

At the beginning of your upkeep, create a 1/1 red Goblin creature token with haste.
Goblin creatures attack each combat if able.

Boulderborn Dragon

Flying, vigilance
Whenever this creature attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Dragon Egg

Defender
When this creature dies, create a 2/2 red Dragon creature token with flying and "{R}: This token gets +1/+0 until end of turn."

Goblin Warchief

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

There and Back Again

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Up to one target creature can't block for as long as you control this Saga. The Ring tempts you.
II — Search your library for a Mountain card, put it onto the battlefield, then shuffle.
III — Create Smaug, a legendary 6/6 red Dragon creature token with flying, haste, and "When Smaug dies, create fourteen Treasure tokens."

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.

Hellkite Charger

Flying, haste
Whenever this creature attacks, you may pay {5}{R}{R}. If you do, untap all attacking creatures and after this phase, there is an additional combat phase.

Quest for the Goblin Lord

Whenever a Goblin you control enters, you may put a quest counter on this enchantment.
As long as this enchantment has five or more quest counters on it, creatures you control get +2/+0.

Dragonlord's Servant

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

Goblin Surprise

Choose one —
• Creatures you control get +2/+0 until end of turn.
• Create two 1/1 red Goblin creature tokens.

Squee, Dubious Monarch

Haste
Whenever Squee attacks, create a 1/1 red Goblin creature token that's tapped and attacking.
You may cast this card from your graveyard by paying {3}{R} and exiling four other cards from your graveyard rather than paying its mana cost.

Shivan Dragon

Flying
{R}: This creature gets +1/+0 until end of turn.

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.

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.

Goblin Gathering

Create a number of 1/1 red Goblin creature tokens equal to two plus the number of cards named Goblin Gathering in your graveyard.