Voltaic Construct, Karn, the Great Creator, and Bag End Banquet

Prerequisites

• Voltaic Construct on the battlefield
• Karn, the Great Creator on the battlefield
• Bag End Banquet on the battlefield

Steps

1. Animate Bag End Banquet using Karn, the Great Creator
2. Activate Bag End Banquet by tapping it, adding Activate Voltaic Construct by paying , untapping Bag End Banquet
3. Repeat from step 2

Results

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