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

Toph, the First Metalbender

Ugin's Nexus

Meticulous Excavation

Ravenous Intruder

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 Ravenous Intruder 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 Ravenous Intruder ability.
6. Activate Meticulous Excavation by paying 2, returning Ugin's Nexus from the battlefield to your hand.
7. Repeat each turn.

This cunning engine bends the rules of time and metallurgy by turning Ugin's Nexus into a land via Toph, the First Metalbender's static ability, allowing Toph's delayed return effect to trigger whenever the Nexus leaves the battlefield. By using Ravenous Intruder to sacrifice the Nexus, its replacement effect safely exiles it instead of letting it hit the graveyard, instantly granting you an extra turn while Toph brings it right back into play. To keep the loop going on demand, Meticulous Excavation steps in to bounce the Nexus back to your hand if you need to replay it, ensuring you can repeat this sequence indefinitely.