Empty the Warrens

Create two 1/1 red Goblin creature tokens.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

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.

Battle Cry Goblin

{1}{R}: Goblins you control get +1/+0 and gain haste until end of turn.
Whenever Battle Cry Goblin 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.

Sarpadian Empires, Vol. VII

As Sarpadian Empires, Vol. VII enters, choose white Citizen, blue Camarid, black Thrull, red Goblin, or green Saproling.
{3}, {T}: Create a 1/1 creature token of the chosen color and type.

Goblin Test Pilot

Flying
{T}: Goblin Test Pilot deals 2 damage to any target chosen at random.

Beetleback Chief

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

Dragonshift

Until end of turn, target creature you control becomes a blue and red Dragon with base power and toughness 4/4, loses all abilities, and gains flying.
Overload {3}{U}{U}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Goblin Banneret

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