Nim Deathmantle, Ashnod's Altar, and Thopter Mechanic

Prerequisites

• Nim Deathmantle on the battlefield
• Ashnod's Altar on the battlefield
• Thopter Mechanic on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing Thopter Mechanic, adding
2. Thopter Mechanic dies, triggering itself and Nim Deathmantle
3. Resolve the Thopter Mechanic trigger, creating a 1/1 Thopter artifact creature token
4. Activate Ashnod's Altar by sacrificing the Thopter, adding
5. Resolve the Nim Deathmantle trigger from step 2, causing you to pay to return Thopter Mechanic 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