Mortuary + Krark-Clan Ironworks + Ornithopter + Gwenom, Remorseless

Mortuary

Krark-Clan Ironworks

Ornithopter

Gwenom, Remorseless

How it works

1. Activate Krark-Clan Ironworks by sacrificing Ornithopter
2. When Ornithopter dies, Mortuary triggers, putting Ornithopter from your graveyard onto the top of your library.
3. Cast Ornithopter from the top of your library by paying 0 life.
4. Repeat.

This loop relies on Krark-Clan Ironworks to convert our free artifacts into a steady stream of colorless mana. To fuel this indefinitely, Mortuary intercepts Ornithopter the moment it hits the graveyard, neatly tucking it back onto the top of our library instead. Meanwhile, Gwenom, Remorseless grants us the crucial permission needed to replay that very same Ornithopter straight from the library's top, letting us bypass traditional mana costs entirely by trading life instead.