Mikaeus, the Unhallowed + Bloodied Ghost + Blasting Station

Mikaeus, the Unhallowed

Bloodied Ghost

Blasting Station

How it works

1. Activate Blasting Station by tapping it and sacrifiicing Bloodied Ghost.
2. When Bloodied Ghost dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it. When it enters, Bloodied Ghost will put a -1/-1 counter on itself, removing the +1/+1 counter.
3. Blasting Station triggers, untapping it.
4. Resolve the Blasting Station ability from step 1.
5. Repeat.