Muldrotha, the Gravetide + Ugin's Nexus + Isochron Scepter + Pull from Eternity + Megatog

Muldrotha, the Gravetide

Ugin's Nexus

Isochron Scepter

Pull from Eternity

Megatog

How it works

1. Activate Megatog by sacrificing Ugin's Nexus, giving it +3/+3 until end of turn.
2. When Ugin's Nexus is sacrificed, it is exiled instead of being put into your graveyard, causing you to take an extra turn after this one.
3. Move to your next turn.
4. Activate Isochron Scepter by paying 2 and tapping it, casting a copy of Pull from Eternity without paying its mana cost.
5. Resolve Pull from Eternity, putting Ugin's Nexus from exile into your graveyard.
6. Cast Ugin's Nexus from your graveyard by paying 5.
7. Repeat.

This clever loop leverages Muldrotha, the Gravetide to continually recast a sacrificed artifact from the graveyard, bypassing its normal final resting place. The engine relies on Ugin's Nexus going to the graveyard to trigger its extra turn, but because Megatog sacrifices it, the Nexus exiles itself instead—protecting your future turns while setting up the loop. From there, Isochron Scepter holds the key by repeatedly casting Pull from Eternity, which snatches Ugin's Nexus right back out of exile and drops it into the graveyard, ready for Muldrotha to play it all over again.