Swamp

Goblin Grenade

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

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

Add {R} for each Goblin on the battlefield.

Return target Goblin card from your graveyard to your hand.

{R}: Goblin Balloon Brigade gains flying until end of turn.

{T}: Goblin Fireslinger deals 1 damage to target player or planeswalker.

Sacrifice a Goblin: Regenerate target creature.

When Festering Goblin dies, target creature gets -1/-1 until end of turn.

Haste
Goblin spells and Rogue spells you cast cost {1} less to cast.

When Goblin Matron enters the battlefield, you may search your library for a Goblin card, reveal that card, put it into your hand, then shuffle.

Enchant land
As long as enchanted land is a basic Mountain, Goblin creatures get +0/+2.

Goblins you control and Elementals you control have menace. (They can't be blocked except by two or more creatures.)