Toph, the First Metalbender + Ugin's Nexus + Meticulous Excavation + Krark-Clan Grunt

Toph, the First Metalbender

Ugin's Nexus

Meticulous Excavation

Krark-Clan Grunt

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