Mortuary + Shilgengar, Sire of Famine + Crimson Kobolds + Bolas's Citadel

Mortuary

Shilgengar, Sire of Famine

Crimson Kobolds

Bolas's Citadel

How it works

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

This crafty loop hinges on Shilgengar, Sire of Famine letting you continually sacrifice Crimson Kobolds to generate Blood tokens, while Mortuary steps in to instantly recycle those sacrificed Kobolds right back to the top of your library. From there, Bolas's Citadel allows you to play the Kobolds directly off the top of your library for zero mana and zero life, letting you seamlessly restart the sacrifice cycle. Because Crimson Kobolds costs nothing and has a mana value of zero, Bolas's Citadel pays no life for the cast, creating an airtight engine that endlessly repeats to flood the board with infinite artifacts, triggers, and death events.