Nim Deathmantle, Ashnod's Altar, and Mighty Mutanimals

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Mighty Mutanimals on the battlefield
• available

Steps

1. Activate Ashnod's Altar by sacrificing Mighty Mutanimals, adding
2. When Mighty Mutanimals dies, Nim Deathmantle triggers, causing you to pay to return Mighty Mutanimals from your graveyard to the battlefield and attach Nim Deathmantle to it
3. When Mighty Mutanimals enters, it triggers, creating a creature token
4. Activate Ashnod's Altar by sacrificing a creature token, adding
5. Repeat

Results

• Infinite +1/+1 counters on creatures you control
• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers