Athreos, Shroud-Veiled, Resourceful Defense, and Ashnod's Altar

Prerequisites

• Athreos, Shroud-Veiled on the battlefield
• Resourceful Defense on the battlefield
• Ashnod's Altar on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing the creature with a coin counter on it
2. When the creature dies, Resourceful Defense and Athreos trigger
3. Resolve the Resourceful Defense trigger, putting a coin counter on another nontoken creature you control
4. Resolve the Athreos trigger, returning the creature that died in step 1 from your graveyard to the battlefield
5. Repeat

Results

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