Karn, the Great Creator, Voltaic Construct, and Chromatic Orrery

Prerequisites

• Karn, the Great Creator on the battlefield
• Voltaic Construct on the battlefield
• Chromatic Orrery on the battlefield
• Chromatic Orrery does not have summoning sickness

Steps

1. Activate Karn's first loyalty ability, causing Chromatic Orrery to become an artifact creature until end of turn
2. Activate Chromatic Orrery by tapping it, adding
3. Activate Voltaic Construct by paying , untapping Chromatic Orrery
4. Repeat from step 2

Results

• Infinite card draw
• Infinite colored mana
• Infinite colorless mana