Mortuary + Fecundity + Cryptic Trilobite

Mortuary

Fecundity

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 Fecundity.
3. Resolve the Mortuary trigger, putting Cryptic Trilobite from your graveyard onto the top of your library.
4. Resolve the Fecundity trigger, causing you to draw a card, thus drawing Cryptic Trilobite from your library.
5. Repeat.

By casting Cryptic Trilobite for zero mana, you instantly send it to the graveyard as a state-based action due to its 0 toughness, which triggers both Mortuary and Fecundity simultaneously. Mortuary ensures that the doomed Trilobite immediately returns straight to the top of your library, while Fecundity allows you to draw that very same card into your hand. This creates a tight, self-sustaining loop that generates infinite enters-the-battlefield events, leaves-the-battlefield events, death triggers, draw triggers, and storm count for any format where these cards are legal.