Mortuary + Vivien, Monsters' Advocate + Hangarback Walker

Mortuary

Vivien, Monsters' Advocate

Hangarback Walker

How it works

1. Cast Hangarback Walker either from your hand or from the top of your library by paying 0.
2. Hangarback Walker enters the battlefield and dies as a state-based action due to having zero toughness.
3. Mortuary triggers, putting Hangarback Walker on top of your library from your graveyard.
4. Repeat.

This engine achieves an infinite loop by casting Hangarback Walker for zero mana, allowing it to immediately hit the graveyard with zero toughness and trigger Mortuary to recycle it straight back to the top of your library. Meanwhile, Vivien, Monsters' Advocate provides the crucial top-deck infrastructure that lets you peer into the future and continuously recast the Walker without ever needing it in your hand. Because Hangarback Walker keeps looping between the battlefield and your library, you can rack up infinite creature entries, exits, and death triggers on demand.