Mortuary + Harvester of Souls + Cryptic Trilobite

Mortuary

Harvester of Souls

Cryptic Trilobite

How it works

1. Cast Cryptic Trilobite by paying 0.
2. Cryptic Trilobite 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 Cryptic Trilobite from your graveyard onto the top of your library.
4. Resolve the Harvester of Souls trigger, causing you to draw a card, thus drawing Cryptic Trilobite from your library.
5. Repeat.

This clever loop turns the zero-toughness entry of Cryptic Trilobite into an endless engine of sacrifice and rebirth. Because you cast it for zero mana, Cryptic Trilobite immediately hits the graveyard, triggering Mortuary to seamlessly place the creature back on top of your library. Simultaneously, Harvester of Souls watches nontoken creatures perish and rewards each death by letting you draw a card, putting Cryptic Trilobite right back into your hand to be replayed.