Screams from Within, Altar of Dementia, and Quintorius, Field Historian

Prerequisites

• Screams from Within on the battlefield
• Altar of Dementia on the battlefield
• Quintorius, Field Historian on the battlefield

Steps

1. Activate Altar of Dementia by sacrificing the creature that has Screams from Within attached
2. When the creature dies, Screams from Within triggers, returning it from your graveyard to the battlefield attached to another creature you control
3. Quintorius triggers, creating a creature token
4. Resolve the Altar of Dementia ability
5. Repeat

Results

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