Toph, the First Metalbender + Toph, Hardheaded Teacher + Ashnod's Altar + Arid Archway

Toph, the First Metalbender

Toph, Hardheaded Teacher

Ashnod's Altar

Arid Archway

How it works

1. Cast the artifact by paying 0.
2. Toph, Hardheaded Teacher triggers, earthbending Arid Archway.
3. Resolve the artifact spell.
4. Activate Ashnod's Altar by sacrificing Arid Archway.
5. When Arid Archway dies, Toph, Hardheaded Teach triggers, returning Arid Archway from your graveyard to the battlefield tapped.
6. When Arid Archway 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. Repeat.

This clever loop relies on Toph, the First Metalbender transforming your cheap artifacts into lands, allowing Arid Archway to bounce them right back to your hand when it enters the battlefield. As you recast that artifact, Toph, Hardheaded Teacher triggers to continuously earthbend your Arid Archway into a creature, making it prime fodder for Ashnod's Altar. Sacrificing the animated land to the altar generates the colorless mana you need to fuel the loop while triggering its own return to the battlefield, setting up an endless cycle of artifact casting, land-bouncing, and sacrifice.