This clever loop centers around Agatha's Soul Cauldron eating Farmstead Gleaner from the graveyard, granting its untap-and-counter ability to Yurlok of Scorch Thrash via a +1/+1 counter. Once empowered, Yurlok of Scorch Thrash can repeatedly tap to add mana and untap itself using the absorbed Farmstead Gleaner ability, growing infinitely large while flooding every player's mana pool. Because Yurlok of Scorch Thrash also dictates that unspent mana turns into life loss as phases change, you can simply let the accumulated mana drain your opponents' life totals down to zero.