Woe Strider + Grazing Kelpie + Hardened Academic

Woe Strider

Grazing Kelpie

Hardened Academic

How it works

1. Activate Woe Strider by sacrificing Grazing Kelpie.
2. When Grazing Kelpie 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 Grazing Kelpie.
4. Resolve the Woe Strider ability.
5. Repeat.