Heartstone reduces the cost of your creatures' activated abilities by one mana.
Pay two mana to exile Palinchron and Village Bell Ringer with Livio
Activate Livio's ability to return Palinchron and Village Bell Ringer to the battlefield
When Palinchron enters the battlefield, untap seven lands
When Village Bell Ringer enters the battlefield, untap Livio
Repeat the process for infinite mana.