Lurrus of the Dream-Den, Kaya's Ghostform, Pitiless Plunderer, and Altar of Dementia

Prerequisites

• Lurrus of the Dream-Den on the battlefield
• Kaya's Ghostform on the battlefield
• Pitiless Plunderer on the battlefield
• Altar of Dementia on the battlefield

Steps

1. Activate Altar of Dementia by sacrificing Lurrus of the Dream-Den
2. When Lurrus of the Dream-Den dies, Kaya's Ghostform and Pitiless Plunderer trigger
3. Resolve the Kaya's Ghostform trigger, returning Lurrus of the Dream-Den from your graveyard to the battlefield
4. Resolve the Pitiless Plunderer trigger, creating a Treasure token
5. Resolve the Altar of Dementia ability, causing target player to mill cards equal to Lurrus of the Dream-Den's power
6. Activate the Treasure by tapping and sacrificing it, adding
7. Cast Kaya's Ghostform from your graveyard by paying , attaching it to Lurrus of the Dream-Den
8. Repeat

Results

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