Archon of Falling Stars + Necromancy + Spawning Pit

Archon of Falling Stars

Necromancy

Spawning Pit

How it works

1. Activate Spawning Pit by sacrificing Archon of Falling Stars.
2. When Archon of Falling Stars dies, it triggers, returning Necromancy from your graveyard to the battlefield.
3. When Necromancy enters the battlefield, it triggers, returning Archon of Falling Stars from your graveyard to the battlefield, and attaching Necromancy to it.
4. Resolve the Spawning Pit ability
5. Repeat.