Mortuary + Bolas's Citadel + Carrion Feeder + Haywire Mite

Mortuary

Bolas's Citadel

Carrion Feeder

Haywire Mite

How it works

1. Activate Carrion Feeder by sacrificing Haywire Mite.
2. When Haywire Mite dies, it and Mortuary triggers.
3. Resolve the Mortuary trigger, putting Haywire Mite from your graveyard onto the top of your library.
4. Resolve the Haywire Mite trigger, causing you to gain 2 life
5. Resolve the Carrion Feeder ability.
6. Cast Haywire Mite from the top of your library by paying 1 life due to Bolas's Citadel.
7. Repeat.

This looping engine lets you endlessly recast a single creature by turning its life cost into a net-positive life swing. Carrion Feeder acts as the sacrifice outlet that feeds your creature into the graveyard, where Mortuary immediately catches it and places it right back on top of your library. From there, Bolas's Citadel allows you to bypass mana costs entirely and cast the creature straight from the library by paying just 1 life. The beauty of the loop is completed by Haywire Mite, whose death trigger conveniently gains you 2 life each iteration—outpacing the life you pay to the Citadel, growing the Feeder infinitely large, and generating limitless storm count and triggers along the way.