Nim Deathmantle, Ashnod's Altar, and Breya, Etherium Shaper

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Breya, Etherium Shaper on the battlefield
• available

Steps

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

Results

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