Mortuary + Skirk Prospector + Bolas's Citadel + Venerated Stormsinger

Mortuary

Skirk Prospector

Bolas's Citadel

Venerated Stormsinger

How it works

1. Activate Skirk Prospector by sacrificing it.
2. When Skirk Prospector dies, Mortuary and Venerated Stormsinger trigger.
3. Resolve the Mortuary trigger, putting Skirk Prospector from your graveyard onto the top of your library.
4. Resolve the Venerated Stormsinger trigger, causing you to gain 1 life and each opponent to lose 1 life.
5. Cast Skirk Prospector from the top of your library by paying 1 life.
6. Repeat.

This loop is a masterclass in recursion, turning the top of your library into an endless revolving door for a single Goblin. With Bolas's Citadel providing the crucial ability to play spells directly from the top of your library by paying life instead of mana, you can recast Skirk Prospector the moment Mortuary places it back on top of your library following a sacrifice. Every single iteration of this cycle fuels your red mana pool via Skirk Prospector's sacrifice ability, while simultaneously triggering Venerated Stormsinger's death ability to drain your opponents' life totals and pad your own life total to keep paying Bolas's Citadel's costs.