Archon of Falling Stars and Blasting Station on the battlefield.
Steps
Activate Blasting Station by tapping it and sacrificing Archon of Falling Stars.
When Archon of Falling Stars dies, it triggers, returning Necromancy from your graveyard to the battlefield.
When Necromancy enters the battlefield, it triggers, returning Archon of Falling Stars from your graveyard to the battlefield, and attaching Necromancy to it.
When Archon of Falling Stars enters the battlefield, Blasting Station triggers, untapping Blasting Station.
Resolve the Blasting Station ability from step 1, putting a +1/+1 counter on it.