Magistrate's Scepter + Energy Chamber + Lithoform Engine

Magistrate's Scepter

Energy Chamber

Lithoform Engine

How it works

1. Activate Magistrate's Scepter, removing 3 charge counters to take an extra turn.
2. Activate Lithoform Engine, copying the extra turn ability.
3. Pass the turn.
4. At the beginning of your upkeep, Energy Chamber triggers, putting a charge counter on Magistrate's Scepter.
5. Activate Magistrate's Scepter, putting a charge counter on itself.
6. Activate Lithoform Engine, copying the trigger.
7. Pass the turn.
8. Repeat.