Underworld Breach, Stitcher's Supplier, and Phyrexian Altar

Prerequisites

• Underworld Breach on the battlefield
• Stitcher's Supplier on the battlefield
• Phyrexian Altar on the battlefield

Steps

1. Activate Phyrexian Altar by sacrificing Stitcher's Supplier, adding
2. Stitcher's Supplier dies, causing you to mill three cards
3. Cast Stitcher's Supplier for its escape cost by paying and exling three other cards from your graveyard
4. Stitcher's Supplier enters the battlefield, causing you to mill three cards
5. Repeat

Results

• Infinite self-mill
• Near-infinite death triggers
• Near-infinite ETB
• Near-infinite LTB
• Near-infinite sacrifice triggers
• Near-infinite storm count