Mortuary + Bile Urchin + Bolas's Citadel + Relic Vial

Mortuary

Bile Urchin

Bolas's Citadel

Relic Vial

How it works

1. Activate Bile Urchin by sacrificing it.
2. When Bile Urchin dies, Mortuary and Relic Vial trigger.
3. Resolve the Mortuary trigger, putting Bile Urchin 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 Bile Urchin ability.
6. Cast Bile Urchin from the top of your library by paying 1 life.
7. Repeat.

This clever loop turns a humble goblin into an inescapable doom by pairing Bolas's Citadel with Mortuary to create a self-sustaining recycling machine off the top of your library. Whenever you sacrifice Bile Urchin to drain your opponents, Mortuary immediately catches it on its way to the graveyard and stacks it right back on top for the Citadel to cast again for a mere 1 life. Meanwhile, Relic Vial acts as the ultimate amplifier, passively turning every single death into an extra life for you and more life loss for your foes.