Cryptic Trilobite enters and dies as a state-based action due to having 0 toughness, triggering Mortuary and High-Society Hunter.
Resolve the Mortuary trigger, putting Cryptic Trilobite from your graveyard onto the top of your library.
Resolve the High-Society Hunter trigger, causing you to draw a card, thus drawing Cryptic Trilobite from your library.
Repeat.
This elegant loop transforms the tragic fate of a zero-toughness creature into an endless cycle of rebirth and discovery. By casting Cryptic Trilobite for zero mana, it immediately succumbs to state-based actions upon entering the battlefield, sending it straight to the graveyard and triggering Mortuary to seamlessly return it to the top of your library. Meanwhile, High-Society Hunter watches this continuous demise, turning every death trigger into a draw trigger that instantly puts Cryptic Trilobite right back into your hand to start the cycle anew.