Voltaic Construct, Living Brain, Mechanical Marvel, and Gilded Lotus

Prerequisites

• Voltaic Construct on the battlefield
• Living Brain, Mechanical Marvel on the battlefield
• Gilded Lotus on the battlefield

Steps

1. Animate Gilded Lotus using Living Brain
2. Activate Gilded Lotus by tapping it, adding three mana of any color Activate Voltaic Construct by paying , untapping Gilded Lotus
3. Repeat from step 2

Results

• Infinite colored mana
• Infinite untap of artifact creatures you control