Screams from Within, and Historian's Boon

Prerequisites

• Screams from Within in hand
• Historian's Boon on the battlefield
• available

Steps

1. Cast Screams from Within by paying , attaching it to a creature with toughness equal to 1
2. The creature dies as a state-based action due to having 0 toughness
3. Historian's Boon and Screams from Within trigger
4. Resolve the Historian's Boon trigger, creating a creature token
5. Resolve the Screams from Within trigger, returning it from your graveyard to the battlefield attached to the creature token Repeat from step 2

Results

• Infinite creature ETB
• Infinite creature LTB
• Infinite death triggers