Toph, the First Metalbender + Toph, Hardheaded Teacher + Carrion Feeder + Dimir Aqueduct

Toph, the First Metalbender

Toph, Hardheaded Teacher

Carrion Feeder

Dimir Aqueduct

How it works

1. Cast the artifact by paying 0.
2. Toph, Hardheaded Teacher triggers, earthbending Dimir Aqueduct.
3. Resolve the artifact spell.
4. Activate Carrion Feeder by sacrificing Dimir Aqueduct.
5. When Dimir Aqueduct dies, Toph, Hardheaded Teach triggers, returning Dimir Aqueduct from your graveyard to the battlefield tapped.
6. When Dimir Aqueduct enters, it triggers, returning the artifact cast in step 1 from the battlefield to your hand, as it's a land due to Toph, the First Metalbender.
7. Resolve the Carrion Feeder ability
8. Repeat.

This clever loop transforms a zero-mana artifact into an infinite engine by leveraging Toph, the First Metalbender, which turns your nontoken artifacts into lands. Once that passive identity shift is active, casting the artifact lets Toph, Hardheaded Teacher earthbend your Dimir Aqueduct into a land-creature, making it an eligible sacrifice for Carrion Feeder. When the Aqueduct hits the graveyard, Toph's earthbend clause returns it to the battlefield tapped, triggering its own bounce ability to pick the artifact back up to your hand so you can cast it all over again.