Ashnod's Altar, Wingrattle Scarecrow, and Thran Vigil

Prerequisites

• Ashnod's Altar on the battlefield
• Wingrattle Scarecrow on the battlefield
• Thran Vigil on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing Wingrattle Scarecrow
2. When Wingrattle Scarecrow dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
3. Thran Vigil triggers, putting a +1/+1 counter on Wingrattle Scarecrow
4. Repeat

Results

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