Mortuary + Bolas's Citadel + Goblin Firestarter + Relic Vial

Mortuary

Bolas's Citadel

Goblin Firestarter

Relic Vial

How it works

1. Activate Goblin Firestarter by sacrificing it.
2. When Goblin Firestarter dies, Mortuary and Relic Vial trigger.
3. Resolve the Mortuary trigger, putting Goblin Firestarter from your graveyard onto the top of your library.
4. Resolve the Relic Vial trigger, causing you to gain 1 life and each opponent to lose 1 life.
5. Resolve the Goblin Firestarter ability.
6. Cast Goblin Firestarter from the top of your library by paying 1 life.
7. Repeat.

This elegant loop turns a humble 1-mana creature into a lethal storm by turning your library into a repeating cradle of life and death. With Bolas's Citadel allowing you to bypass mana costs and cast Goblin Firestarter directly from the top of your library for just 1 life, Mortuary steps in to immediately recycle the goblin back to the top of your library whenever it perishes. Meanwhile, Relic Vial acts as the ultimate pay-off; as long as you control a Cleric, its static ability ensures that every single sacrifice drains your opponents and replenishes the life you spent, fueling the Citadel's payment engine indefinitely.