Reaping Willow, Ashnod's Altar, Agatha's Soul Cauldron, and Chaos Spewer

Prerequisites

• Reaping Willow on the battlefield
• Ashnod's Altar on the battlefield
• Agatha's Soul Cauldron on the battlefield
• Chaos Spewer in the graveyard
• available

Steps

1. Activate Reaping Willow by paying due to Agatha's Soul Cauldron and removing two counters from it, returning Chaos Spewer from your graveyard to the battlefield
2. When Chaos Spewer enters, it triggers
3. Choose not to pay and put two -1/-1 counters on Reaping Willow
4. Activate Ashnod's Altar by sacrificing Chaos Spewer, adding
5. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers