Mortuary + Lithatog + Ornithopter + Gwenom, Remorseless

Mortuary

Lithatog

Ornithopter

Gwenom, Remorseless

How it works

1. Activate Lithatog by sacrificing Ornithopter
2. When Ornithopter dies, Mortuary triggers, putting Ornithopter from your graveyard onto the top of your library.
3. Resolve the Lithatog ability.
4. Cast Ornithopter from the top of your library by paying 0 life.
5. Repeat.

This clever engine centers around Lithatog, which uses its ability to feed on artifacts and sacrifice Ornithopter to start the loop. The moment Ornithopter hits the graveyard, Mortuary instantly intercepts it and redirects the tiny automaton right back to the top of your library. That is where Gwenom, Remorseless comes in: its attack trigger lets you look at and play cards from the top of your library, paying life instead of mana costs. Because Ornithopter costs zero mana, you can cast it repeatedly for zero life, feeding Lithatog indefinitely while generating endless death and entry triggers.