Basalt Monolith, and Forensic Gadgeteer

Prerequisites

• Basalt Monolith on the battlefield
• Forensic Gadgeteer on the battlefield

Steps

1. Activate Basalt Monolith's first activated ability by tapping it, adding
2. Activate Basalt Monolith's last ability by paying , untapping it
3. Repeat

Results

• Infinite colorless mana