Mortuary + Shilgengar, Sire of Famine + Memnite + Bolas's Citadel

Mortuary

Shilgengar, Sire of Famine

Memnite

Bolas's Citadel

How it works

1. Activate Shilgengar by sacrificing Memnite
2. When Memnite dies, Mortuary triggers, putting Memnite from your graveyard onto the top of your library.
3. Resolve the Shilgengar ability.
4. Cast Memnite from the top of your library by paying 0 life.
5. Repeat.

This loop turns Shilgengar, Sire of Famine into an engine for infinite sacrifice and leave-the-battlefield triggers by leveraging the zero-mana cost of Memnite. Each time you sacrifice Memnite to Shilgengar, Mortuary catches it on its way to the graveyard and neatly places it right back on top of your library. From there, Bolas's Citadel allows you to recast Memnite immediately for zero life, feeding the cycle anew while generating endless Blood tokens.