Stalwart Successor, Goblin Bombardment, and Twilight Shepherd

Prerequisites

• Stalwart Successor on the battlefield
• Goblin Bombardment on the battlefield
• Twilight Shepherd on the battlefield

Steps

1. Activate Goblin Bombardment by sacrificing Twilight Shepherd When Twilight Shepherd dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
2. When Twilight Shepherd enters, Stalwart Successor triggers, putting a +1/+1 counter on Twilight Shepherd Resolve the Goblin Bombardment ability
3. Repeat

Results

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