Voltaic Construct + Faeburrow Elder + Thran Forge

Voltaic Construct

Faeburrow Elder

Thran Forge

How it works

1. Cause Faeburrow Elder to become an artifact using Thran Forge.
2. Activate Faeburrow Elder by tapping it, adding at least 3
3. Activate Voltaic Construct by paying 2, untapping Faeburrow Elder.
4. Repeat from step 2.

By using Thran Forge to turn Faeburrow Elder into an artifact, we transform the Elder from a simple mana producer into a valid target for Voltaic Construct's untap ability. Once the transformation is complete, Faeburrow Elder's second ability taps it for at least three mana—more than enough to pay the two mana required by Voltaic Construct to untap it, leaving you with extra mana left over. Repeating this loop allows you to continuously tap and untap your newly minted artifact creature to generate infinite colored mana.