Stalwart Successor + Viscera Seer + Putrid Goblin

Stalwart Successor

Viscera Seer

Putrid Goblin

How it works

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