Palinchron in exile (has a takeover counter on it).
The Master in hand or in the command zone.
You control up to seven lands that can tap to produce at least ({2} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) .
You have enough mana to pay for commander tax beyond the first ({4} magic symbol) , if applicable.
Steps
Activate up to seven lands by tapping them, adding at least ({2} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) .
Cast The Master either from your hand or from the command zone by paying ({U} magic symbol) ({B} magic symbol) and commander tax, if applicable, choosing to have it enter the battlefield as a copy of Palinchron.
When The Master enters the battlefield, it triggers, untapping up to seven lands.
Activate up to seven lands by tapping them, adding at least ({2} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) .
Activate The Master by paying ({2} magic symbol) ({U} magic symbol) ({U} magic symbol) , returning it to your hand from the battlefield.
Repeat from step 2.
If lands you control can tap to produce at least ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) , this combo nets infinite mana.