Mikaeus, the Unhallowed + Blasting Station + Reluctant Dounguard

Mikaeus, the Unhallowed

Blasting Station

Reluctant Dounguard

How it works

1. Activate Blasting Station by tapping it and sacrificing Reluctant Dounguard.
2. When Reluctant Dounguard dies, its undying ability triggers, returning it from your graveyard to the battlefield without a +1/+1 counter on it due to its replacement effect.
3. When Reluctant Dounguard enters, Blasting Station triggers, untapping Blasting Station.
4. Resolve the Blasting Station ability from step 1
5. Repeat.