Voltaic Construct + Encroaching Mycosynth + Rofellos, Llanowar Emissary

Voltaic Construct

Encroaching Mycosynth

Rofellos, Llanowar Emissary

How it works

1. Activate Rofellos by tapping it, adding at least .
2. Activate Voltaic Construct by paying 2, untapping Rofellos.
3. Repeat

This elegant loop turns Rofellos, Llanowar Emissary into an absolute powerhouse by leaning heavily on Encroaching Mycosynth, which crucially redefines Rofellos as an artifact in addition to its other types. Because Rofellos is now an artifact creature, it becomes a legal target for Voltaic Construct's ability, allowing you to pump green mana into the Construct to untap the elf. As long as Rofellos yields enough green mana per tap to comfortably pay the two-mana untap cost—which is easily managed when you control multiple Forests—you can repeat this sequence indefinitely to generate infinite green mana and infinite untaps.