Toph, the First Metalbender + Toph, Hardheaded Teacher + Lithatog + Selesnya Sanctuary

Toph, the First Metalbender

Toph, Hardheaded Teacher

Lithatog

Selesnya Sanctuary

How it works

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

This clever engine thrives on Toph, the First Metalbender's passive ability, which turns all your nontoken artifacts into lands. With this land-type blanket in place, playing a zero-cost artifact triggers Toph, Hardheaded Teacher to animate Selesnya Sanctuary via earthbend. You then sacrifice that land-artifact to Lithatog, sending Selesnya Sanctuary to the graveyard. Its death triggers Toph, Hardheaded Teacher's return effect, bringing Selesnya Sanctuary right back to the battlefield tapped. Finally, Selesnya Sanctuary's own enter-the-battlefield trigger bounces the original zero-cost artifact back to your hand because the artifact is now treated as a land, allowing you to replay it and loop the entire sequence infinitely.