Voltaic Key, Rings of Brighthearth, and Chromatic Orrery

Prerequisites

• Voltaic Key on the battlefield
• Rings of Brighthearth on the battlefield
• Chromatic Orrery on the battlefield

Steps

1. Activate Chromatic Orrery's first activated ability, adding to your mana pool
2. Activate Voltaic Key by paying and tapping it, targeting Chromatic Orrery
3. Rings of Brighthearth triggers, allowing you to pay to copy Voltaic Key's ability
4. Resolve the copied ability, untapping Voltaic Key
5. Resolve the ability from step 2, untapping Chromatic Orrery
6. Repeat any number of times
7. Once you have infinite mana, you may repeat the loop targeting any artifact in step 2, and/or activating Chromatic Orrery's last ability in step 1

Results

• Infinite card draw
• Infinite colored mana
• Infinite colorless mana
• Infinite untap of artifacts you control