Voltaic Key + Rings of Brighthearth + Metalworker

Prerequisites

• 2 or more artifacts in hand.
• Metalworker does not have summoning sickness.

Steps

1. 1Activate Metalworker and reveal 2 artifacts to add to your mana pool.
2. 2Activate Voltaic Key to untap Metalworker.
3. 3Rings of Brighthearth triggers allowing you to copy Voltaic Key's ability and untap Voltaic key with the copy.
4. 4Repeat.

Effects

• Infinite colorless mana
• Infinite mana artifacts you control can produce
• Infinite untap of artifacts you control