Voltaic Construct + Prismatic Geoscope + March of the Machines

Voltaic Construct

Prismatic Geoscope

March of the Machines

How it works

1. Activate Prismatic Geoscope by tapping it, adding at least three mana of any color
2. Activate Voltaic Construct by paying 2, untapping Prismatic Geoscope.
3. Repeat

By transforming every noncreature artifact into an artifact creature with power and toughness equal to its mana value, March of the Machines allows Prismatic Geoscope to be targeted by abilities that care about artifact creatures. This lets you tap the Geoscope for a bounty of colored mana thanks to its Domain ability, fueling the activation cost of Voltaic Construct. In turn, the Construct's ability untaps the Geoscope so you can repeat the process indefinitely, turning a modest mana investment into infinite colored mana.