Nim Deathmantle, Ashnod's Altar, and Ishkanah, Grafwidow

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Ishkanah, Grafwidow on the battlefield
• available

Steps

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

Results

• Infinite colorless mana
• Infinite creature tokens
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers