Mortuary + Bile Urchin + Bolas's Citadel + Al Bhed Salvagers

Mortuary

Bile Urchin

Bolas's Citadel

Al Bhed Salvagers

How it works

1. Activate Bile Urchin by sacrificing it.
2. When Bile Urchin dies, Mortuary and Al Bhed Salvagers trigger.
3. Resolve the Mortuary trigger, putting Bile Urchin from your graveyard onto the top of your library.
4. Resolve the Al Bhed Salvagers trigger, causing you to gain 1 life and target 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 ingenious loop transforms the life-paying drawback of Bolas's Citadel into an engine for victory by turning the top of your library into an endless armory. When you sacrifice Bile Urchin to drain your opponent, Mortuary immediately catches the creature as it hits the graveyard, neatly stacking it back onto the top of your library just in time for Bolas's Citadel to let you recast it for a mere 1 life. Meanwhile, Al Bhed Salvagers acts as a crucial life-gain buffer, offsetting the cost of casting the Urchin over and over until your opponent's life total is completely whittled away.