Sigil of the New Dawn, Pawn of Ulamog, Phyrexian Altar, and Ornithopter

Prerequisites

• Sigil of the New Dawn on the battlefield
• Pawn of Ulamog on the battlefield
• Phyrexian Altar on the battlefield
• Ornithopter on the battlefield

Steps

1. Activate Phyrexian Altar by sacrificing Ornithopter, adding
2. Pawn of Ulamog and Sigil of the New Dawn trigger
3. Resolve the Pawn of Ulamog trigger, creating a 0/1 Eldrazi Spawn creature token
4. Activate the Eldrazi Spawn by sacrificing it, adding
5. Resolve the Sigil of the New Dawn trigger, causing you to pay to return Ornithopter from your graveyard to your hand
6. Cast Ornithopter by paying
7. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite storm count