This loop turns a simple artifact creature into an infinite mechanical engine by exploiting the interaction between a 0-mana cost and graveyard-stacking rules. When you cast Phyrexian Marauder for zero mana, it instantly hits the battlefield with zero toughness and dies as a state-based action, immediately triggering Mortuary to place it right back on top of your library. From there, Vivien, Monsters' Advocate steps in to provide the necessary top-deck visibility and permission, allowing you to seamlessly cast the Marauder again and again straight off the library. Because the Marauder costs nothing to deploy, you can repeat this sequence indefinitely to farm infinite death triggers, enter-the-battlefield events, and storm count.