Cacophony Scamp

Whenever Cacophony Scamp deals combat damage to a player, you may sacrifice it. If you do, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
When Cacophony Scamp dies, it deals damage equal to its power to any target.

Have

Hordeling Outburst

Create three 1/1 red Goblin creature tokens.

The Autonomous Furnace

The Autonomous Furnace enters tapped.
{T}: Add {R}.
{1}{R}, {T}, Sacrifice The Autonomous Furnace: Draw a card.

Krenko's Command

Create two 1/1 red Goblin creature tokens.

Goblin Grenade

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

Mountain

Guttersnipe

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

Mudbutton Torchrunner

When Mudbutton Torchrunner dies, it deals 3 damage to any target.

Improvised Club

As an additional cost to cast this spell, sacrifice an artifact or creature.
Improvised Club deals 4 damage to any target.

Lightning Strike

Lightning Strike deals 3 damage to any target.

Goblin Arsonist

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

Dragon Fodder

Heartfire

As an additional cost to cast this spell, sacrifice a creature or planeswalker.
Heartfire deals 4 damage to any target.

Barrage of Expendables

{R}, Sacrifice a creature: Barrage of Expendables deals 1 damage to any target.

Goblin War Strike

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

Footlight Fiend

When Footlight Fiend dies, it deals 1 damage to any target.

Artillerize

As an additional cost to cast this spell, sacrifice an artifact or creature.
Artillerize deals 5 damage to any target.

Goblin Fireleaper

{1}{R}: Goblin Fireleaper gets +1/+0 until end of turn.
When Goblin Fireleaper dies, it deals damage equal to its power to target creature an opponent controls.

Tarfire

Fireblade Charger

As long as Fireblade Charger is equipped, it has haste.
When Fireblade Charger dies, it deals damage equal to its power to any target.

Collateral Damage

As an additional cost to cast this spell, sacrifice a creature.
Collateral Damage deals 3 damage to any target.