Eternal Witness, Phyrexian Altar, and Kaya's Ghostform

Prerequisites

• Eternal Witness on the battlefield
• Phyrexian Altar on the battlefield
• Kaya's Ghostform on the battlefield
• Kaya's Ghostform attached to Eternal Witness

Steps

1. Activate Phyrexian Altar by sacrificing Eternal Witness, adding
2. When Eternal Witness dies, Kaya's Ghostform triggers, returning Eternal Witness from your graveyard to the battlefield
3. When Eternal Witness enters the battlefield, it triggers, returning Kaya's Ghostform from your graveyard to your hand
4. Cast Kaya's Ghostform by paying
5. Repeat

Results

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