Basalt Monolith, Does Machines, and Agatha of the Vile Cauldron

Prerequisites

• Basalt Monolith on the battlefield
• Does Machines on the battlefield
• Agatha of the Vile Cauldron on the battlefield

Steps

1. Cause Basalt Monolith to become a creature using Does Machines
2. Activate Basalt Monolith's first ability by tapping it, adding
3. Activate Basalt Monolith's last ability by paying , untapping it
4. Repeat from step 2

Results

• Infinite colorless mana