Toph, the First Metalbender + Haru, Hidden Talent + Stonework Puma + Grinding Station

Toph, the First Metalbender

Haru, Hidden Talent

Stonework Puma

Grinding Station

How it works

1. Cast Stonework Puma by paying 3.
2. When Stonework Puma enters, Grinding Station and Haru trigger.
3. Resolve the Haru trigger, targeting Stonework Puma as it is a land due to Toph.
4. Resolve the Grinding Station trigger, untapping it.
5. Activate Grinding Station by tapping it and sacrificing Stonework Puma.
6. When Stonework Puma dies, Haru triggers, returning Stonework Puma from your graveyard to the battlefield tapped.
7. When Stonework Puma enters, Grinding Station and Haru trigger.
8. Resolve the Haru trigger, targeting Stonework Puma as it is a land due to Toph.
9. Resolve the Grinding Station trigger, untapping it.
10. Resolve the Grinding Station ability from step 5.
11. Repeat from step 5.

This ingenious loop transforms your artifact creatures into a self-sustaining engine by letting Toph, the First Metalbender turn every nontoken artifact you control into a land. When you cast Stonework Puma, its arrival triggers both Haru, Hidden Talent to earthbend it and Grinding Station to untap itself. You can then sacrifice the Puma to activate Grinding Station's mill ability, which triggers Haru's return-to-the-battlefield effect because the Puma is secretly a land in the graveyard. This endless cycle of sacrifice and rebirth mills your opponents out while generating infinite enters-the-battlefield and death triggers.