Nim Deathmantle, Ashnod's Altar, and Doctor Doom

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Doctor Doom on the battlefield
• available

Steps

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

Results

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