Isochron Scepter + Final Fortune + Sundial of the Infinite

Isochron Scepter

Final Fortune

Sundial of the Infinite

How it works

1. Activate Isochron Scepter by paying 2, casting a copy of Final Fortune without paying its mana cost.
2. Resolve the Final Fortune, taking an extra turn after this one.
3. At the beginning of each extra turn's end step, Final Fortune triggers.
4. Holding priority, activate Sundial of the Infinite by paying 1 and tapping it, ending the turn.
5. Repeat.