Underworld Breach + Stitcher's Supplier + Infernal Plunge + Urn of Godfire

Underworld Breach

Stitcher's Supplier

Infernal Plunge

Urn of Godfire

How it works

1. Cast Infernal Plunge for its escape cost by paying , exling three other cards from your graveyard, and sacrificing Stiticher's Supplier.
2. When Stitcher's Supplier dies, it triggers, causing you to mill three cards.
3. Resolve Infernal Plunge, adding .
4. Activate Urn of Godfire's first ability by paying 2, adding .
5. Cast Stitcher's Supplier for its escape cost by paying and exling three other cards from your graveyard.
6. When Stitcher's Supplier enters the battlefield, it triggers, causing you to mill three cards.
7. Repeat.

This loop relies on Underworld Breach to turn your graveyard into an active hand, allowing you to repeatedly cast your threats for their escape costs. You fuel this engine by sacrificing Stitcher's Supplier to pay for Infernal Plunge, which both triggers the Supplier to mill three cards and yields a surplus of red mana. Meanwhile, Urn of Godfire acts as a color-fixing conduit by turning generic mana into the black mana required to recast the Supplier from your graveyard. As you continuously loop these pieces, Stitcher's Supplier mills your entire library while keeping your graveyard constantly stocked with fodder for the next escape.