Viscera Seer + Wingrattle Scarecrow + Thran Vigil

Viscera Seer

Wingrattle Scarecrow

Thran Vigil

How it works

1. Activate Viscera Seer 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. Thran Vigil triggers, putting a +1/+1 counter on Wingrattle Scarecrow.
4. Resolve the Viscera Seer ability.
5. Repeat.