Woe Strider + Wingrattle Scarecrow + Hardened Academic

Woe Strider

Wingrattle Scarecrow

Hardened Academic

How it works

1. Activate Woe Strider 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. Hardened Academic triggers, putting a +1/+1 counter on Wingrattle Scarecrow.
4. Resolve the Woe Strider ability.
5. Repeat.