This intricate loop transforms the battlefield into an engine of endless rebirth, centered around the dual nature of Eirdu, Carrier of Dawn and Isilu, Carrier of Twilight; once its back face is active, your nontoken creatures are granted persist, ready to return from the grave when they perish. The real trick to bypassing persist's usual limitation lies in Vizier of Remedies, whose replacement effect ensures that those returning creatures enter completely clean of -1/-1 counters. To set the cycle in motion, Umbral Collar Zealot provides the sacrificial outlet needed to send your creatures to the graveyard in the first place, triggering their return while letting you surveil through your library.