Decaying Soil + Phyrexian Altar + Shield Sphere

Decaying Soil

Phyrexian Altar

Shield Sphere

How it works

1. Cast Shield Sphere by paying 0.
2. Activate Phyrexian Altar by sacrificing Shield Sphere, adding 1.
3. When Shield Sphere dies, Decaying Soil triggers, causing you to pay 1 to return Shield Sphere to your hand from your graveyard.
4. Repeat.

This clever loop relies on the zero-mana cost of Shield Sphere to get the engine rolling, letting you feed it directly into Phyrexian Altar to generate a steady stream of mana, storm count, and death triggers. Ordinarily, sending your artifact to the graveyard would be a permanent loss, but Decaying Soil is waiting in the wings to recycle it; once you've crossed the threshold of seven cards in your graveyard, that enchantment's passive triggered ability gives you the option to pay the exact mana you just generated to return Shield Sphere right back to your hand. By constantly recasting the zero-cost defender and sacrificing it again and again, you sustain a perpetual motion machine fueled entirely by graveyard synergy.