Mortuary + Krark-Clan Ironworks + Phyrexian Walker + Bolas's Citadel

Mortuary

Krark-Clan Ironworks

Phyrexian Walker

Bolas's Citadel

How it works

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

This elegant loop turns zero-mana artifacts into an endless engine of sacrifice and rebirth. By using Krark-Clan Ironworks to recycle Phyrexian Walker for colorless mana, you fuel the death triggers that Mortuary relies on to continuously place the Walker back on top of your library. From there, Bolas's Citadel steps in as the mastermind, allowing you to cast the Phyrexian Walker straight from the library for zero life over and over again.