Blasting Station + Hardened Academic

Blasting Station

Hardened Academic

How it works

1. Activate Blasting Station by tapping it and sacrificing the creature with persist.
2. When that creature dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Hardened Academic and Blasting Station trigger.
4. Resolve the Blasting Station trigger, untapping it.
5. Resolve the Hardened Academic trigger, putting a +1/+1 counter on the persist creature.
6. Remove a +1/+1 counter and a -1/-1 counter from that creature as a state-based action.
7. Resolve the Blasting Station ability from step 1.
8. Repeat.