Stalwart Successor + Grinding Station + Wingrattle Scarecrow

Stalwart Successor

Grinding Station

Wingrattle Scarecrow

How it works

1. Activate Grinding Station by tapping it and 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, Grinding Station and Stalwart Successor trigger.
4. Resolve the Grinding Station trigger, untapping it
5. Resolve the Stalwart Successor trigger, putting a +1/+1 counter on Wingrattle Scarecrow
6. Resolve the Grinding Station ability from step 1
7. Repeat.