Stalwart Successor, Ashnod's Altar, and Wingrattle Scarecrow

Prerequisites

• Stalwart Successor on the battlefield
• Ashnod's Altar on the battlefield
• Wingrattle Scarecrow on the battlefield

Steps

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

Results

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