Ultron, Artificial Malevolence, Voltaic Construct, and Arc Reactor

Prerequisites

• Ultron, Artificial Malevolence on the battlefield
• Voltaic Construct on the battlefield
• Arc Reactor in hand
• plus up to an additional available

Steps

1. Cast Arc Reactor by paying its mana cost, reduced by its improvise cost if desired
2. When Arc Reactor enters, Ultron triggers, causing you to pay to create a copy of Arc Reactor that is a 2/2 Robot Villain creature
3. During your next turn, activate the Arc Reactor token by tapping it, adding Activate Voltaic Construct by paying , untapping the Arc Reactor token
4. Repeat from step 3

Results

• Infinite colorless mana