Mortuary + Memnite + Bolas's Citadel + Carrion Feeder

Mortuary

Memnite

Bolas's Citadel

Carrion Feeder

How it works

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

This ingenious engine turns a free zero-mana artifact creature into an infinite storm and sacrifice resource. With Bolas's Citadel allowing you to cast spells directly from the top of your library by paying life instead of mana, you can repeatedly deploy Memnite for zero life. When you sacrifice that Memnite to Carrion Feeder to grow its power with +1/+1 counters, Mortuary immediately intercepts it, placing the creature right back on top of your library so Bolas's Citadel can play it once more.