Nim Deathmantle, Ashnod's Altar, and Mitotic Slime

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Mitotic Slime on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing Mitotic Slime, adding
2. When Mitotic Slime dies, it and Nim Deathmantle trigger, Resolve the Mitotic Slime trigger, creating two 2/2 Ooze creature tokens
3. Holding priority, activate Ashnod's Altar by sacrificing an Ooze, adding
4. When the Ooze dies, it triggers, creating two 1/1 Ooze creature tokens
5. Resolve the Nim Deathmantle trigger, causing you to pay to return Mitotic Slime from your graveyard to the battlefield and attach Nim Deathmantle to it
6. Repeat

Results

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