Toph, the First Metalbender + Ugin's Nexus + Meticulous Excavation + Thaumatog

Toph, the First Metalbender

Ugin's Nexus

Meticulous Excavation

Thaumatog

How it works

1. Cast Ugin's Nexus by paying 5.
2. At the beginning of your end step, Toph triggers, causing Ugin's Nexus to become an artifact land creature.
3. Activate Thaumatog by sacrificing Ugin's Nexus. Ugin's Nexus is exiled instead of being put into your graveyard, causing you to take an extra turn after this one.
4. Toph triggers, returning Ugin's Nexus from exile to the battlefield.
5. Resolve the Thaumatog ability.
6. Activate Meticulous Excavation by paying 2, returning Ugin's Nexus from the battlefield to your hand.
7. Repeat each turn.

This clever loop hinges on Toph, the First Metalbender transforming your non-token artifacts into lands, allowing Thaumatog to treat Ugin's Nexus as a land sacrifice. Because Ugin's Nexus is sent to exile rather than the graveyard when sacrificed, its replacement effect triggers to grant you an extra turn, while Toph's lingering land-type return safety net seamlessly pulls it back to the battlefield. From there, Meticulous Excavation provides the mana-fueled way to return Ugin's Nexus right back to your hand so you can recast it and chain infinite extra turns.