Toph, the First Metalbender + Toph, Hardheaded Teacher + Simic Growth Chamber + Phantom Train

Toph, the First Metalbender

Toph, Hardheaded Teacher

Simic Growth Chamber

Phantom Train

How it works

1. Cast the artifact by paying 0.
2. Toph, Hardheaded Teacher triggers, earthbending Simic Growth Chamber.
3. Resolve the artifact spell.
4. Activate Phantom Train by sacrificing Simic Growth Chamber.
5. When Simic Growth Chamber dies, Toph, Hardheaded Teach triggers, returning Simic Growth Chamber from your graveyard to the battlefield tapped.
6. When Simic Growth Chamber 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 Phantom Train ability
8. Repeat.

This clever loop turns a seemingly innocuous zero-mana artifact into an infinite engine by weaving together type-changing mechanics and self-correcting triggers. Toph, the First Metalbender does the heavy lifting of turning your nontoken artifacts into lands, allowing Simic Growth Chamber to treat them as valid bounce targets while also letting Toph, Hardheaded Teacher's earthbend abilities animate your bounce lands. By sacrificing that animated Simic Growth Chamber to Phantom Train, you trigger its death-and-return safety net, which then loops your zero-mana artifact right back to your hand to start the cycle anew.