Coretapper + Magistrate's Scepter + Mortuary

Coretapper

Magistrate's Scepter

Mortuary

How it works

1. During your upkeep step, 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.
3. When Coretapper dies, Mortuary triggers, putting Coretapper from your graveyard on top of your library.
4. Resolve the Coretapper ability, putting two charge counters on Magistrate's Scepter.
5. Move to your draw phase, drawing Coretapper from the top of your library.
6. Cast Coretapper by paying 1.
7. Activate Magistrate's Scepter's second ability by tapping it and removing three charge counters from it, taking an extra turn after this one.
8. Repeat each turn.

This elegant loop allows you to bend time to your absolute will, granting you infinite turns and locking your opponent out of the game entirely. Each cycle begins by leveraging Coretapper to rapidly stack charge counters onto Magistrate's Scepter, using both its tapping ability and its sacrifice ability. The moment Coretapper is sacrificed, Mortuary steps in to neatly recycle the automaton right back to the top of your library, ensuring you can easily redraw and recast it on your next turn. With Magistrate's Scepter now holding enough charges to activate its second ability and claim an extra turn, you simply repeat the process indefinitely.