Stalwart Successor + Goblin Bombardment + River Kelpie

Stalwart Successor

Goblin Bombardment

River Kelpie

How it works

1. Activate Goblin Bombardment by sacrificing River Kelpie
2. When River Kelpie dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When River Kelpie enters, it and Stalwart Successor trigger.
4. Resolve the River Kelpie trigger, causing you to draw a card
5. Resolve the Stalwart Successor trigger, putting a +1/+1 counter on River Kelpie
6. Resolve the Goblin Bombardment ability.
7. Repeat.