Voltaic Construct, Karn, the Great Creator, and Everflowing Chalice

Prerequisites

• Voltaic Construct on the battlefield
• Karn, the Great Creator on the battlefield
• Everflowing Chalice on the battlefield

Steps

1. Animate Everflowing Chalice using Karn, the Great Creator
2. Activate Everflowing Chalice by tapping it, adding at least Activate Voltaic Construct by paying , untapping Everflowing Chalice
3. Repeat from step 2

Results

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