By using Rise and Shine's overload mode, you turn your Arc Reactor into an artifact creature, allowing it to benefit from its own mana-producing capabilities and the untap loop. Once animated, you tap Arc Reactor to generate three colorless mana, which more than comfortably pays the two-mana cost to activate Voltaic Construct and untap the Reactor. This creates a self-sustaining engine that yields infinite colorless mana.