Mortuary + Ashnod's Altar + Shield Sphere + Gwenom, Remorseless

Mortuary

Ashnod's Altar

Shield Sphere

Gwenom, Remorseless

How it works

1. Activate Ashnod's Altar by sacrificing Shield Sphere
2. When Shield Sphere dies, Mortuary triggers, putting Shield Sphere from your graveyard onto the top of your library.
3. Cast Shield Sphere from the top of your library by paying 0 life.
4. Repeat.

This clever loop turns the zero-cost Shield Sphere into an infinite engine by leveraging Ashnod's Altar to generate endless colorless mana while feeding your graveyard. Because Shield Sphere goes straight to the graveyard when sacrificed, Mortuary steps in to instantly recycle it right back to the top of your library. From there, Gwenom, Remorseless grants you permission to cast cards directly from the top of your library, allowing you to replay the Shield Sphere for zero mana (and zero life) over and over again.