Zacama, Primal Calamity + Panharmonicon + Shivan Wurm

Zacama, Primal Calamity

Panharmonicon

Shivan Wurm

How it works

1. Activate all mana-producing lands you control by tapping them, adding at least 4.
2. Cast Zacama either from your hand or from the command zone by paying 6 plus commander tax, if applicable.
3. When Zacama enters the battlefield, it triggers twice.
4. Resolve the first trigger, untapping all lands you control.
5. Activate all mana-producing lands you control by tapping them, adding at least 4.
6. Resolve the second Zacama trigger, untapping all lands you control.
7. Cast Shivan Wurm by paying 3.
8. When Shivan Wurm enters the battlefield, it triggers twice, returning itself and Zacama from the battlefield to your hand.
9. Repeat.
10. If lands you control can tap to produce at least 5, this combo nets infinite mana, and you may use that mana to activate Zacama's other abilities.