Old One Eye, Nim Deathmantle, and Ashnod's Altar

Prerequisites

• Old One Eye on the battlefield
• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• available

Steps

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

Results

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