Underworld Breach, Stitcher's Supplier, Infernal Plunge, and Gemstone Array

Prerequisites

• Underworld Breach on the battlefield
• Stitcher's Supplier on the battlefield
• Infernal Plunge in the graveyard
• Gemstone Array on the battlefield
• You have at least three additional cards in your graveyard
• available

Steps

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 Gemstone Array's first ability by paying , putting a charge counter on it
5. Activate Gemstone Array's second ability by removing a charge counter from it, adding
6. Cast Stitcher's Supplier for its escape cost by paying and exling three other cards from your graveyard
7. When Stitcher's Supplier enters the battlefield, it triggers, causing you to mill three cards
8. Repeat

Results

• Infinite self-mill