Archon of Falling Stars + Animate Dead + Phyrexian Altar

Archon of Falling Stars

Animate Dead

Phyrexian Altar

How it works

1. Activate Phyrexian Altar by sacrificing Archon of Falling Stars, adding one mana of any color.
2. When Archon of Falling Stars dies, it triggers, returning Animate Dead from your graveyard to the battlefield.
3. When Animate Dead enters the battlefield, it triggers, returning Archon of Falling Stars from your graveyard to the battlefield, and attaching Animate Dead to it.
4. Repeat.

This elegant loop leverages Phyrexian Altar to convert Archon of Falling Stars into a steady stream of any-color mana. When the Archon hits the graveyard, its triggered ability plucks Animate Dead right back out of the yard to restart the cycle. That returning Aura then resolves its own enter-the-battlefield trigger to bring the Archon straight back to the battlefield, ready to be sacrificed once more.