This ingenious loop uses Grinding Station as the engine to continuously mill your opponents by sacrificing and re-casting a single artifact creature. Thanks to Mortuary, the sacrificed Phyrexian Walker goes right back to the top of your library instead of staying in the graveyard, ready to be deployed again. Gwenom, Remorseless is the crucial enabler that lets you peer into the future and cast that Phyrexian Walker straight from the top of your library, trading life instead of mana—which costs you a cool zero. Every time the artifact creature re-enters the battlefield, Grinding Station untaps itself to repeat the cycle infinitely, churning out endless enters-the-battlefield, death, and sacrifice triggers.