Magistrate's Scepter, Lithoform Engine, Karn's Bastion, and Doubling Season

Prerequisites

• Magistrate's Scepter on the battlefield
• Lithoform Engine on the battlefield
• Karn's Bastion on the battlefield
• Doubling Season on the battlefield
• Magistrate's Scepter has at least one charge counter on it
• each odd-numbered turn, with available each even-numbered turn available

Steps

1. Activate Karn's Bastion's second ability by paying and tapping it
2. Holding priority, activate Lithoform Engine's first ability by paying and tapping it, copying Karn's Bastion's ability
3. Resolve both Karn's Bastion abilities, putting four charge counters on Magistrate's Scepter
4. Activate Magistrate's Scepter's second ability by tapping it and removing three charge counters from it, causing you to take an extra turn after this one
5. Move to your next turn
6. Activate Karn's Bastion's second ability by paying and tapping it, putting two charge counters on Magistrate's Scepter
7. Repeat steps 4 and 5 one time
8. Repeat from step 1

Results

• Infinite turns