Mortuary + Garruk's Horde + Walking Ballista

Mortuary

Garruk's Horde

Walking Ballista

How it works

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

This loop turns the top of your library into an infinite-firing automaton factory, fueled by the relentless recycling of Mortuary. By casting Walking Ballista for zero mana, you immediately send it to the graveyard, which triggers Mortuary to place it right back on top of your library. From there, Garruk's Horde steps in as the mastermind, letting you continuously cast that very same Walking Ballista straight off the top of your library without ever needing it in your hand. The result is an endless cascade of enters-the-battlefield, leaves-the-battlefield, and death events that can easily overwhelm your opponents.