Emry, Lurker of the Loch + Coretapper + Magistrate's Scepter

Emry, Lurker of the Loch

Coretapper

Magistrate's Scepter

How it works

1. Activate Coretapper's first ability by tapping it, putting a charge counter on Magistrate's Scepter.
2. Activate Coretapper's second ability by sacrificing it, putting two charge counters on Magistrate's Scepter.
3. Activate Magistrate's Scepter's second ability by tapping it and removing three charge counters from it, taking an extra turn after this one.
4. Activate Emry by tapping them, allowing you to cast Coretapper from your graveyard this turn.
5. Cast Coretapper by paying 2.
6. Repeat each turn.