Voltaic Construct + Mycosynth Lattice + Accomplished Alchemist

Voltaic Construct

Mycosynth Lattice

Accomplished Alchemist

How it works

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

The magic of this loop lies in Mycosynth Lattice, which transforms every permanent on the battlefield—including Accomplished Alchemist—into an artifact in addition to its other types. This brilliant piece of type-changing infrastructure allows Voltaic Construct to target and untap Accomplished Alchemist for a mere two mana. Once you tap Accomplished Alchemist to generate the required mana using its ability, you simply feed a portion of that energy back into Voltaic Construct to untap it, netting surplus mana with every single iteration.