Mortuary, Bolas's Citadel, Carrion Feeder, and Sifa Grent

Prerequisites

• Mortuary on the battlefield
• Bolas's Citadel on the battlefield
• Carrion Feeder in hand
• Sifa Grent on the battlefield

Steps

1. Cast Carrion Feeder by paying its mana cost
2. Activate Carrion Feeder by sacrificing it
3. When Carrion Feeder dies, Mortuary and Sifa Grent trigger
4. Resolve the Mortuary trigger, putting Carrion Feeder from your graveyard onto the top of your library
5. Resolve the Sifa Grent trigger, causing target opponent to lose 1 life and you to gain 1 life
6. Cast Carrion Feeder from the top of your library by paying 1 life
7. Repeat from step 2

Results

• Infinite creature ETB
• Infinite creature LTB
• Infinite death triggers
• Infinite lifegain triggers
• Infinite lifeloss
• Infinite creature sacrifice triggers
• Infinite storm count