Toph, the First Metalbender + Toph, Hardheaded Teacher + Umbral Collar Zealot + Guildless Commons

Toph, the First Metalbender

Toph, Hardheaded Teacher

Umbral Collar Zealot

Guildless Commons

How it works

1. Cast the artifact by paying 0.
2. Toph, Hardheaded Teacher triggers, earthbending Guildless Commons.
3. Resolve the artifact spell.
4. Activate Umbral Collar Zealot by sacrificing Guildless Commons.
5. When Guildless Commons dies, Toph, Hardheaded Teach triggers, returning Guildless Commons from your graveyard to the battlefield tapped.
6. When Guildless Commons 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 Umbral Collar Zealot ability
8. Repeat.

This intricate loop transforms cheap artifacts into a self-sustaining engine by letting Toph, the First Metalbender turn all your nontoken artifacts into lands. With that foundation set, you can cast a zero-mana artifact to trigger Toph, Hardheaded Teacher and earthbend Guildless Commons into a creature-land, which Umbral Collar Zealot can then sacrifice. Thanks to Toph, Hardheaded Teacher's safety net, sacrificing Guildless Commons triggers its return to the battlefield, where its own entry trigger bounces the original artifact back to your hand so the whole cycle can begin anew.