Osgir, the Reconstructor + Isochron Scepter + Pull from Eternity + Gonti's Aether Heart

Osgir, the Reconstructor

Isochron Scepter

Pull from Eternity

Gonti's Aether Heart

How it works

1. Activate Osgir's second ability by paying 6, tapping it and exiling Gonti's Aether Heart from your graveyard, creating two token copies of Gonti's Aether Heart.
2. Put one of the Gonti's Aether Hearts into your graveyard due to the legend rule.
3. Both Gonti's Aether Hearts' enters-the-battlefield ability trigger twice, adding a total of eight E.
4. Activate the remaining Gonti's Aether Heart by paying eight E and exiling it, causing you to take an extra turn after this one.
5. Activate Isochron Scepter by paying 2 and tapping it, casting a copy of Pull from Eternity without paying its mana cost.
6. Resolve Pull from Eternity, putting Gonti's Aether Heart into your graveyard from exile.
7. Repeat each turn.