Blasting Station + Hardened Academic + Obstinate Gargoyle

Blasting Station

Hardened Academic

Obstinate Gargoyle

How it works

1. Activate Blasting Station by tapping it and sacrificing Obstinate Gargoyle.
2. When Obstinate Gargoyle 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 Hardened Academic trigger, putting a +1/+1 counter on Obstinate Gargoyle.
5. Resolve the Blasting Station trigger, untapping it.
6. Resolve the Blasting Station ability from step 1.
7. Repeat.