Mortuary + Ugin's Conjurant + Harvester of Souls

Mortuary

Ugin's Conjurant

Harvester of Souls

How it works

1. Cast Ugin's Conjurant by paying 0.
2. Ugin's Conjurant enters and dies as a state-based action due to having 0 toughness, triggering Mortuary and Harvester of Souls.
3. Resolve the Mortuary trigger, putting Ugin's Conjurant from your graveyard onto the top of your library.
4. Resolve the Harvester of Souls trigger, causing you to draw a card, thus drawing Ugin's Conjurant from your library.
5. Repeat.

This clever loop turns the zero-cost casting of Ugin's Conjurant into a self-sustaining engine by exploiting its zero toughness, causing it to instantly perish as a state-based action upon entry. Each time it hits the graveyard, Mortuary cleanly redirects it right back to the top of your library instead of letting it rest. Meanwhile, Harvester of Souls watches the carnage, turning every single one of those deaths into a brand new card draw that immediately puts Ugin's Conjurant back into your hand to start the cycle anew.