Mortuary + Bolas's Citadel + Fanatical Firebrand + Embalmed Ascendant

Mortuary

Bolas's Citadel

Fanatical Firebrand

Embalmed Ascendant

How it works

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

This loop turns a humble goblin into an engine of endless attrition by completely bypassing traditional mana costs. With Bolas's Citadel allowing you to cast spells directly from the top of your library for life instead of mana, Fanatical Firebrand can be sacrificed to ping any target and immediately recurred thanks to Mortuary placing it back on top of your library. Meanwhile, Embalmed Ascendant acts as the vital catalyst that ensures every iteration is net-positive on life: its max speed ability triggers upon the creature's death to recoup the life spent on the Citadel while draining your opponents down to zero.