Mortuary + Bolas's Citadel + Carrion Feeder + Funeral Room // Awakening Hall

Mortuary

Bolas's Citadel

Carrion Feeder

Funeral Room // Awakening Hall

How it works

1. Activate Carrion Feeder by sacrificing it.
2. When Carrion Feeder dies, Mortuary and Funeral Room // Awakening Hall trigger.
3. Resolve the Mortuary trigger, putting Carrion Feeder from your graveyard onto the top of your library.
4. Resolve the Funeral Room // Awakening Hall trigger, causing you to gain 1 life and each opponent to lose 1 life.
5. Resolve the Carrion Feeder ability.
6. Cast Carrion Feeder from the top of your library by paying 1 life.
7. Repeat.

This looping mechanism transforms a humble Carrion Feeder into a self-sustaining engine by turning its own death back into a free rebirth. Whenever you sacrifice the Feeder, Mortuary ensures the creature immediately returns to the top of your library rather than lingering in the graveyard, allowing Bolas's Citadel to cast it right back off the library top for a mere 1 life instead of its mana cost. Meanwhile, Funeral Room // Awakening Hall acts as the ultimate payoff, converting every single iteration of this recycling loop into endless life drain for your opponents and lifegain to effortlessly offset the life paid to the Citadel.