Stalwart Successor + Goblin Bombardment + Wingrattle Scarecrow

Stalwart Successor

Goblin Bombardment

Wingrattle Scarecrow

How it works

1. Activate Goblin Bombardment 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. When Wingrattle Scarecrow enters, Stalwart Successor triggers, putting a +1/+1 counter on Wingrattle Scarecrow
4. Resolve the Goblin Bombardment ability.
5. Repeat.