Mortuary + Vindictive Vampire + Bolas's Citadel + Fanatical Firebrand

Mortuary

Vindictive Vampire

Bolas's Citadel

Fanatical Firebrand

How it works

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

This loop transforms the humble Fanatical Firebrand into an endless engine of destruction, fueled entirely by life rather than mana thanks to Bolas's Citadel. Whenever you sacrifice the Firebrand, Mortuary immediately rescues it from the graveyard by placing it right back on top of your library, where Bolas's Citadel lets you recast it for just 1 life. Meanwhile, Vindictive Vampire quietly watches the carnage, turning every single death into life gained for you and unyielding damage for your opponents until nothing is left standing.