Nim Deathmantle, Ashnod's Altar, and Requiem Angel

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Requiem Angel on the battlefield
• You control an additional nontoken non-Spirit creature

Steps

1. Activate Ashnod's Altar by sacrificing a nontoken non-Spirit creature, adding
2. When the creature dies, Requiem Angel and Nim Deathmantle triggers
3. Resolve the Requiem Angel trigger, creating a 1/1 Spirit creature token
4. Activate Ashnod's Altar by sacrificing the Spirit, adding
5. Resolve the Nim Deathmantle trigger from step 2, causing you to pay to return the non-Spirit creature from your graveyard to the battlefield, and attach Nim Deathmantle to it
6. Repeat

Results

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