Battle-Scarred Goblin

Whenever Battle-Scarred Goblin becomes blocked, it deals 1 damage to each creature blocking it.

Fervor

Creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

Krenko, Mob Boss

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

Mana Geyser

Add {R} for each tapped land your opponents control.

Sneak Attack

{R}: You may put a creature card from your hand onto the battlefield. That creature gains haste. Sacrifice the creature at the beginning of the next end step.

Seething Song

Goblin Assault Team

Haste
When Goblin Assault Team dies, put a +1/+1 counter on target creature you control.

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.