Voltaic Construct + Biotransference + Fanatic of Rhonas

Voltaic Construct

Biotransference

Fanatic of Rhonas

How it works

1. Activate Fanatic of Rhonas by tapping it, adding .
2. Activate Voltaic Construct by paying 2, untapping Fanatic of Rhonas.
3. Repeat

Biotransference does the heavy lifting here by turning Fanatic of Rhonas into an artifact creature, allowing it to be targeted by Voltaic Construct's untap ability. Once the conditions for Fanatic of Rhonas's Ferocious ability are met to yield four green mana per tap, you can spend two of that mana to activate Voltaic Construct and untap the Fanatic. This creates a neat self-sustaining loop that nets infinite green mana and infinite untaps for your entire team.