Screams from Within, Phyrexian Altar, and Quintorius, Field Historian

Prerequisites

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

Steps

1. Activate Phyrexian Altar 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. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite colored mana
• Infinite sacrifice triggers
• Infinite death triggers